The person proposing this, I believe, doesn't understand why there is an issue with this particular 'charity'.
I've looked at the events this organisation runs and there are large red flags with regard to content, attendees and structure of the events - and the description reads as if it is very much aimed at young adults, and people with emotional issues ('safe spaces', sensory spaces, special lighting, lots of messages about how inclusive they are and made up words, etc etc etc).
A member of the team made an interesting comment about 'IF this is the type of organisation we want to be associated with').
How do I raise concerns without the inevitable accusations?