We have at least two 'alternative lifestyle' grouos living in woods nearby, possibly 3. They are all incredibly well organised, one has been there for 15+ years, one has been building up slowly for about 10 years, and (I think) there's another which has been there maybe 5 years - though they may be the same group as the first, not sure.
I have a friend who comes from a big city every few months to spend the weekend with the second group which is why i know it's there, otherwise I wouldn't. Everyone round here knows about the first group, and the third one, assuming it's not just an extension of the first, are very high profile in town, doing building work and carpentry etc. They are extremely good, really really skilled.
None of these groups would have any trouble at all steaming a badger, putting it in and keeping it warm & ready to eat. Two communities do have open kitchens so you could pop along and have a meal for a donation or some work.
I don't have a problem believing any of this. I do wonder where the woods are that are close enough to the Natural History Museum for op's ex to be able to travel there while the meal stays warm, but hey, he could be a one-man tent dweller in somewhere like Oxshot woods or Epping Forest.