35 isn't a request, but a message from a powerful politician to the people behind the sale. It's hard to guess the exact meaning without full context, but I think it's "I know enough. If you want to proceed with the sale, you have to give me the names and I'll send some of them to prison." They may try to call his bluff, but they'll be sorry if he indeed knows something.

Conflict of interest may not generally be illegal, but it can be illegal under specific circumstances, especially if undisclosed. Especially things that get filed with the SEC. I would assume a lot of decisions made at the board and C-suite level have stricter requirements for this.

I believe a 501c3 is bound by their charter which would presumably include this conflict of interest policy. Not doing so could cause loss of non-profit status and probably other fines and penalties.