"They don't have anything to gain from this"

Now hold on, how would you know that? They could have been paid, there are enough people around that want him gone.

The better question is: why care? At this point is there even one single redeeming quality about Donald Trump? He is a war perpetuator, a science denialist, he is working against the western coalition and he put people in place, that are horribly incompetent like Sarah Sanders. Or others that are horribly biased like Jeff Sessions.
I wouldn't even care if every single thing claimed about him is a lie, if those lies end up removing him as president of the USA.
Fuck, I wouldn't even bat an eye if he got run over by a truck at this point.