Or he knew that donating to influential science organizations would buy him good will, put him in touch with other rich donors, be good for media coverage and get him a list of people who might vouch for him when called by a journalist because they've received funding from him.

> This would make claims about his "extraordinary group" of friends make a lot of sense.

I don't know, it sounds like a slightly better worded version of "I know great people, they're the best people really, and I am one of them". They're extraordinary and they are his friends => wow, that must be quite the great guy, or he wouldn't have those kinds of friends.

Scientists might not directly have political influence, but especially the very successful ones are well-connected and have friends in the media. If you have lots of money to spend and you want to buy good will, wouldn't you just spread it? If a journalist ever thinks about you and talks about you at a private party, what better could happen than a science guy saying "oh I know him, he funded our important research" and an author saying "oh, yeah, that guy, he donated money to some literary program" and a finance guy saying "wow, yeah, he's very successful".

I find that a much simpler explanation that fits well into the picture.