It would appear that your view is that he is, by definition, grifting simply because (you allege) he has gone from making money out of trans activism, to the reverse.
I would counter that firstly by suggesting that making money out of training [people and/or companies] is fine, and changing the content of what you teach as you learn new things, consider things differently and have a change of opinion is perfectly fine. I think there are a lot of people (incl. on this board) who did not start out as fully GC.
I do not know his full work history or precisely what he has taught in the past. I do not know if he was ever "running a trans activist organisation", but he seems to have - at a minimum - worked on projects that are "pro trans". If you are able to evidence his precise role and precisely what he was advocating I would love to see it.
From what I can make out he has a background in teaching / education. He has done a lot of work in and around EDI, which means that broadly speaking until 2015 he would not have needed to be doing much trans related stuff at all. By around 2018 he was moving out of the EDI field because of the conflict between trans rights and LGB / women's rights, and because the original purpose of EDI - to ensure meritocracy by ensuring underprivileged minorities were not overlooked - was being replaced by equity (quotas for minorities, potentially illegal, to ensure diversity, but not diversity of thought).
As far as I can see the potential legitimate criticisms relate to what he might have been doing 2015-2018 (when loads of us had not spotted the dangers of TQ+ ideology, and bearing in mind I have no evidence he was ever pushing for trans privileges such as men in women's spaces or that gay men should be open to dating TIFs). I suspect / believe that the whole reason he is doing what he is doing now is because he is a teacher by trade, he needs to earn a living, and he was forced out of his previous role because he could not support the way trans/EDI was going. I KNOW that he 100% believes that sex is real and matters and TQ+ ideology is incredibly dangerous.