OP, I'm really sorry to hear about the circumstances leading to this question being asked. This is a terrible set of circumstances leading you here. For one, I applaud you for even finding your way here and taking it upon yourself to figure out a way ahead.
I can't really answer your questions, as asked, as I am not able to provide you with medical advice over the internet. What I can say is this: in 2016, I had a Right Ulnar Collateral Ligament Reconstruction with anterior transposition of the ulnar nerve, and a osteophyte excision from the olecranon process. I had lost about 5 degrees of extension prior to the surgery, but I came of out surgery lacking about 20+ degrees of extension. As a Physical Therapist, and the only PT at my location at the time with the know-how to rehab a Tommy John Surgery patient, I was left to rehab myself. I used absolutely nothing but the starting strength novice linear progression to rehab myself. I currently lack about 10 degrees of extension, and I am not likely to achieve full extension ever. Tightness in surgically treated elbows is pandemic.
I started rehab shortly after the surgery, and within 12 weeks of surgery, I was back to bench pressing over 300 which was higher than my pre-surgical PR. I had surgery three years ago, and my personal best is now 385 at a bodyweight of 172. I have really done nothing but barbell training since the surgery and I am stronger than I ever have been before. I have absolutely zero pain in my elbow. And.....this is not the typical prognosis for someone with this surgery. The typical TJS patient is a dice roll on whether they return or not. I am an Orthopaedic Clinical Specialist Physical Therapist. That is what I do for a living, and when I had to treat myself, I used the SS NLP, without any modifications, and I am where I am today because of it.