Medical Waiver question

[Turbobalaclava]

I have a couple of questions about medical waivers.

I am 27 now but when I was 19 I had knee surgery. Basically I dislocated the knee cap on my left leg on occasion and surgery was done to prevent it from happening again. It has not happened since and in fact I have not had any problems with it. After completing around 9 months of rehab I was cleared to play college athletics. I feel I have a knee that is stronger than before and they only real side affect is a large scar. I am currently running and rucking daily and have not noticed any knee pain, just sore feet, blisters and raw spots on places i am not used to from the ruck.

1) Does anyone have any experience with waivers for similar injuries?

2) If I want to go Option 40 or 18x, does that make getting the waiver much harder?

3) Do I need a waiver at MEPS, then get another one at Airborne, then again at RIP or SFAS?

I searched this site and a few others as well as used google and seem to have conflicting information especially in regards to question 3.

Thanks in advance.