Camp lease question

Cliff Notes edition:
Have a camp on someone else's land. Lease is $600 a year. Been there for 25 years. The ownership of the land has been passed down over the years and currently is divided between multiple family members. In January the family who claims to be the majority owners calls all the lessees saying he wants to sell it....for way more than its worth. We tell him we'd be glad to negotiate purchasing the land at a reasonable price. Then he tells us that he wants us to start paying him instead of the other family member who lives there because he hasn't seen any of the money. I tell him that's not my problem and that I have receipts of where we wired the money to the other family member and texts confirming this. Now he says he is going to put a 10 day eviction notice on our camp if we don't give our physical address (he is from the country and has no idea that he can just pull that info from the WWW). Anyway, I told him that I'd give him the info if he told me why he needed it. He was just belligerent. At this point I don't even think he has deed to the land and he isn't listed on the tax assessment database.
Anyway, long story shot I don't want to lose my camp and I don't want the yahoos to burn it down either. how should I proceed in this situation?