He was part of a non-profit advocacy group that advocated for a specific cause. Some people contributed to that. Seems he ran around doing radio interviews, not making profits.
In a free society, I don't see anything wrong with that.
I'm not even sure if non-profits should be obliged to publicize their donors if the donors don't want to be identified.
Of course, if the work is specifically political, it should be transparent. Also, given that he's going to take a government position, we want to know who he's been taking from ...
While it does maybe look a little suspicious at face value there's no there there.
If a bunch of people want to run around advocating some kind of principle and raise money for themselves to do that then so be it, they can do that.