Long Post Please read help with Advice! SMC Aid and Attendance exam

Hello everyone, (LONG POST BUT PLEASE READ AND HELP)

So I've been browsing this forum for a while and see that there is a lot of knowledge and really good advice so am hoping I can get some insight as well as some advice.

My brother is a disabled veteran I help care for him.
He retired from the Army 2016, 5 years ago in June. Served 3 tours, 2 tours in Iraq, and 1 in Afghanistan. While deployed his job was in mortuary affairs processing of remains so am sure you can only imagine the things on his mind and what he still lives with daily. The military in 2003, 2004, 2009 was not the military it currently is if you mentioned you had issues, like PTSD your career was over.  My brother made it in the Army for 17 years he should have been in my eyes, retired medically.

 Once he returned from his tours he was always getting himself trouble or just having issues with his command. His wife at the time tried so many times to let those in charge of him that he was not right, suffering in silence. Before he retired his command took him to a mental hospital because of statements that he made. Basically he made homicidal statements. He spent 2 weeks in the mental ward. At that time my brother could barely even walk, he would go to work and go see someone in medical and they would send him home to rest. 
When he finally retired after 6 months he got a VA rating of 70% I worked with his wife to help with the kids and his care.  In 2018 we finally got him approved for 100% with TDIU VA benefits and SSDI. At that time of his approval of 100% he only had PTSD at 70% and a bunch of other ratings at different percentages getting him SMC-S.  

Fast forward because I want to provide the information needed but also do not want to make this long.  So while my brother was in Iraq he suffered a TBI he has  a rating for TBI which was at 0% with a couple of other ratings for his residuals of TBI.  So in 2019, his neurologists recommended I open a claim for sleep apnea secondary to both his TBI and PTSD. I did, and I requested that his TBI and PTSD also be looked at by submitting a claim to have the percentages raised.

Well, after 5 CP exams> which were for the following. TBI, Headaches, PTSD,  Central Nerve System, TBI Resduials, Sleep Apnea, Gerd, all of his ratings were looked at.
At our first CP exam, the cp examiner asked why I was not getting SMC for Aid attendance, which to be totally honest I did not know about. My brother wife did try to get approved for the caregiver program and she was denied stating that the program was for Vets that would show improvement over time and that my brother first needed to start seeing a VA therapist for mental problems at the VA.   He was already being seen by the local Vet center by a therapist so he did not want to change and she was trying to manage him and the kids and did not have the fight to keep fighting the system.

Yesterday I looked on healthevet and ebenefits to check the claim and what I saw was the following 
the claim actually went into Gathering Evidence after it was in Pending decision approval about a week half ago but the RATED Disability have changed some of having new date of  7/2019 when I put the claim in:

20% radiculopathy right  lower extremity (femoral)
20% radiculopathy left lower extremity (sciatic)
0% residual Head scar
10% painful head scar
20% radiculopathy left upper extremity (ulnar nerve)
0% TBI ("This was his rating for TBI when he retired")
100% PSTD with TBI ( " PTSD was by itself and at 70% but now it is combined with TBI and at 100% but then my question is why is TBI still listed showing 0%)
30% radiculopathy right upper extremity (ulnar nerve)
20 % radiculopathy left lower extremity (femoral)
10% Tinnitus 
10% Gerd
0% right forearm scar
50% migraines and Vertigo
0% right hip femoral acetabular limitation of extension
10% left hip femoral acetabular limitation of extension
20% Lumbar spine degenerative arthritis 
20% Cervical spine degenerative arthritis
10% painful right knee scar
10% right hip femoral acetabular impingement syndrome with thigh impairment

sleep Apnea looks like it was denied (" I do not know why as I have not received the packet")

All the Nerve ratings went up!

Also in March of this year, we submitted the aid and attendance form 21-2680 we submitted because we did even know about aid attendance was possible and also because when we went to our first CP exam the cp examiner suggested we look into SMC T for aid and attendance.  When we submitted the form my brother's wife and myself wrote letters explaining what we do daily for him, this is what cp examiner recommended.

So my brother wife actually left her job to care for him because when he first retired she would come home from work and either her or the kids would find him on the floor he would fall and just stay there until someone arrived home, he almost burned the kitchen once because he put bread in the toaster and then went to sleep and forget about it, he has been arrested for driving at top speeds of 125 trying to get away from what he says are terrorist. So he no longer drives, she drives him everywhere, but everywhere is his appointments he barely goes out, he has severe rage and anger just can not think properly and even appropriately. Really bad memory problems
She helps him out of bed every morning because his legs are pins and needles she makes sure he brushes his teeth, she showers him and dresses him, makes his meals, he decided he would not eat after the burning of the kitchen toaster, so if she or the kids or me  do not give him food he just will not eat he saw allot of burned bodies so the toaster burning surely triggered something.  she manages his meds because at first he was over medicating or just not taking them. When he wakes up with nightmares talking about the dead bodies he sees she calms him down, he becomes suicidal at times and even makes a lot of homicidal statements. He wants nothing to do with our family other than his wife and kids and me,,,,, he pretty much keeps to himself.  A lot of the guys he served with in Iraq doing the same job as him have committed suicide.  My dad and me try to help him and his wife and the kids as much as we can, if I can give her a break here and there I try to.  We are all in agreement that the man who left for Iraq on his first deployment is no longer the same person.

So to my questions??

1. Yesterday I got a call from LHI that they need to schedule him for AID and Attendance CP exam? I have no idea what this is and how to prepare him for this exam he likes to have knowledge of what his appointments are for? And actually gets very angry when he does not and starts saying he wants to go home!!!

2. If he has one rating at 100% which be PTSD and TBI would the VA consider him for SMC L? If so why do they need an exam if the VA form from his Va dr was provided?

3. Based on the Ratings above what would his SMC rate be if any?

4. Any advice on how to get his sleep apnea service-connected secondary to his PTSD or TBI or both?

5. Also he has ED it's in his medical record and it was asked about that when they did the exams for TBI residuals and Central nerve system, but I see nothing on his ratings ?
I know that how that claim is back to gathering Evidence is not final but if ED is not listed is that something I should fight for him?

Any advice and help would be greatly appreciated.