With this new information about the previous accidents and such, I would suggest seeking out a very good chiropractor.
I don't know if you have thought about that option or not.

But with those other accidents your spine has to have gotten misaligned.
Some MD's just don't suggest or mention Chiropractic for whatever reason.

But there are some very good ones to be found and often less costly that PT sessions.
You could just take your report & films if you have them all, and go for some evaluations to see what a chiro suggests. You don't have to allow any treatment if you aren't sure of it, or them.
Some will do an eval for free and some will work with you if no insurance.