Its pretty boggy up that way so might be tricky finding a dry spot for a tent!
The MBA state that All bothies are closed at the moment. Moesdale cottage is a big place but its normally all locked up anyway apart from one room which is normally open
I can confirm it is a total bogfest at the moment from all approaches, it was grim on Saturday. I did notice a quad making its was to the cottage though.
It's described as closed on the website and that's about as much restriction applies. Wet Sleddale describes the area well, but plenty of higher ground around the valley. Quad bikes do have a habit of getting stuck where walkers can step over.