C&P test procedure for knee exam

What are the different ways examiners can measure RoM of knee extension?

Just got results back from C&P finally (after 5 years) got my left knee connected (just need right knee now).  Nurse practitioner couldn’t get my knee to extend enough in the seated position to get a reading (essentially 0°) next did the flexion test from the lying down position, no problem bringing thigh up to flexion.  Straightening it was a different story, struggled to get it to lay flat (0°-135° flexion, normal range).

Raters denied me RoM for the lousy extension?  I though extension was done from the sitting position.  A previous C&P measured me from the seated position I wrote down what he said; 52° and 60° degrees (right and left knees). If I am correct that is easily 50% for each knee.

What am I missing here?  Is there some special procedure the they have to go through to test.  I  though they were supposed to pick the results that favors the vet.  Not cherry pick testing methods that gives the VA the advantage.  Or am I  totally off base in interpretation of the evaluation?

Unfortunately anxiety is getting the worst of me right now (just put in for increase).  And have been diagnosed with  Functional Neurological Disorder (conversion disorder),  last night while putting the dog out I hobbled with my cain quite literally dragging my right leg (couldn’t get it to work).

Comments, questions, advice…  I  really could use some help right now.