Perhaps it is a solid time to break your training down into focused movements for a while, I think that is always a solid period for any person wanting to maximum size and strength long term and could give your hamstrings much needed rest.
To be honest I personally would be afraid to recommend any free weight leg/quad movement because they will all involve hamstrings to an extent and your hamstring health is an unknown variable to me.
If it was me, I would look at it as an opportunity from the extra overall stress deduction to your system from temporarily stopping squats ect to really hammer some other bodyparts you want to grow. You will probably notice a lot more energy overall and be able to train them harder than ever and make results faster than ever as well.
This lesson was taught to me by Bill Pearl, a man I am lucky enough to call a hero and a friend. I suffer from a lot of illness from an incurable disease, during especially rough bouts of time I cannot train really taxing exercises like deadlifts, squats. cleans ect without getting violently ill. Yet I also always wanted 20 inch arms, although I was stuck for the longest time in the 16-17 range. Pearl told me that if I really wanted to focus on arms he would start to train them 3 days a week( on alternating days) with 12 sets for triceps and 12 for biceps, 6-8 hard reps a set Monday and Friday and 8-12 reps a set Wednesday. I did so the next bout of sickness limiting me from full body movements and the next time I measured my arms ( was over half a year, maybe close to a year) they were just over 19 inches. I have since used such specialized programs for specific bodyparts or lifts for myself and others to great success
I would propose you look at this as an opportunity to do something similar. Maybe you want to really focus on your chest and back, your arms, shoulders, or break a strength plateau with your overhead press, bench, pullup numbers ect. Think about something you would love to do and really focus on that, still training everything else to a degree obviously but making sure you make this possible negative of an injured hamstring to the opportunity to bring you phenomenal results elsewhere.
As for your squat numbers and being close to your all time best I will tell you what people told me everytime I fell ill, muscles have a way to bounce back and you will be just fine ( which I later found out was due to nuclei and mitochondria retention abilities within muscles). I have had two especially bad periods of illness, just in 2016 I could not eat solid food most the year and lost 40 pounds when I was already relatively lean. But you will surprise yourself how well your hamstrings will bounce back after recovering and by making use of the time to really push other areas and limits you may be better off than you ever imagined.
I would also get it professionally looked at it if possible and wish you a speedy recovery. Sorry I could not be of more help but I just wanted to let you know if you do end up having to avoid the area it can still be a great opportunity in the long run.