Out of PT visits but may need a 3rd surgery if I don't rehab properly, really not sure what to do

I could use some advice for a situation with my insurance (f*** UHC), all advice is appreciated.

Back in January I tore my ACL skiing, had surgery in Feb and did aggressive PT in the clinic and at home. In late May my insurance informed my PT I was only covered for 30 visits per year. I started going to PT just once a week and doing more stuff at home. Clearly, what I was doing wasn't enough because over the summer, my surgeon told me I developed a lot of scar tissue preventing my mobility and causing me pain. I had a surgery (arthroscopy and manipulation) done several weeks ago and it feels a bit better, but my doctor wants me back in PT and straight up told me if I don't rehab it correctly, I'll be back in the OR for another procedure. I've been trying to do stretches and exercises on my own but I really don't think it's a substitute for PT.

I've been practically calling UHC every day trying different avenues for more PT visits but at this point I think it's unlikely they cover any more. My next step is to submit an appeal–I already did this back in May but they apparently never received my paperwork by snail-mail.

What the hell am I supposed to do? I need to see a physical therapist to at least figure out how I can do proper exercises on my own, but there's no way I can afford to pay out of pocket. Do I buy a supplementary healthcare plan until the end of the year? How much does that even cost?