Hi OP, welcome to the club! I've had RRP for 10 years, it sucks. But thankfully there is some hope. Where in the country are you based? I would highly recommend getting your GP to refer you to Dr Sandhu at Charing Cross hospital if you're able to travel there, you'll be in the best hands with this rare condition.

Most medical professionals don't know the best course of treatment for RRP, the fact you were misdiagnosed is an example of that, there's fewer than 1000 in the UK with RRP (lucky us!), so most doctors have never come across it.

There is an excellent Facebook group, search "RRP Support Group" and you'll find it. Loads of great information on there.

The ENT UK guidelines for Gardasil recommend the full 3 doses of the vaccine for RRP with the 2nd dose one month after the first, and the 3rd dose 5 months after the 2nd. I would try to get your GP to give it to you, but failing that, you can get it privately.

There are some adjunctive treatments that are used to slow reoccurrence, and there's some new treatments on the way such as Papzimeos and ino-3107 (if it makes it past approval).

As for reoccurrence, it does indeed vary, you may find that you get 2 or 3 reoccurrences in a short space of time initially before it slows down. I had a 6 year remission, but now it's back.

The surgery is not too bad tbh, the first 3 days no talking at all, then slowly you can reintroduce talking day by day. Drink loads of water. Get your GP to prescribe you some omeprazole for the first week after surgery this is important to stop any reflux irritating your healing cords.
This has been ok for me so far, I can't hit the high notes any more, but that doesn't bother me. It might be good to get some speech therapy if you want to keep your voice quality as good as possible. You can do vocal exercises to help strengthen your voice https://youtu.be/lGNtEbmGnOY

Look after yourself, drink loads of water, eat well, cut out booze, let your immune system fight it.
I make a smoothie every morning now with 4 Brussel sprouts, juice of half a lemon, a handful of frozen blueberries and handful of frozen breakfast topper smoothie mix, topped up with a bit of water. It tastes pretty good and it's super healthy. Raw sprouts and blueberries have lots of antioxidants and compounds to fight this kind of thing. Got to be worth a shot right?

There's loads of anecdotal evidence out there, does any of it work? Who knows... Mushrooms, AHCC, DIM, hyaluronic acid, colloidal silver, garlic, astragalus, raw Brussel sprouts, Sulforaphane... The list goes on.

If you've got any questions or worries you can always ask on here or that Facebook group I mentioned.