A very good friend of mine (aged 42) had absolutely shocking RA which pretty much shut down his otherwise very active and sports-driven life. Not even capable of doing the gardening that he loves.
Though I personally don't have RA, I watched in awe as my friend's RA pretty much disappeared and he regained 100% of his previously active life back.
He called it the Pattison Diet. From memory it was somewhere along the lines of the vegan diet you mentioned didn't work but I'm unsure if there was more to it or not.
I do NOT work for them and thank God have no RA but I was astounded at how dramatically my friend sent the RA packing! If this is redundant and you are either healed or happy with your existing situation....fantastic! If Not, I can vouch 100% for the Pattison Diet working beyond belief for a personal friend. Best of luck. Hope this helps....