These people are stupid. If they had left him alone, then it would be far more challenging to break the media hold on the public. They could have more effectively played a "he is playing partisan politics!" Line and possibly leveraged public support.
At least, from where I stand it appears that way. Perhaps there is more to it that compelled them to move so blatantly against Trump. Assuming that Trump's campaign was, in itself, a sting operation, then it can be assumed that there were plenty of people willing to act the part in order to convince the democrats that they either needed to act so brazenly, or to give them room to hang themselves without interruption.
This is the other part of it that many are missing. Some in the departments could have or should have stopped it, but didn't or possibly obeyed under documented protest to cover them in the event it was investigated. Rather than going nuts and blowing the whistle, they filed their complaints as they should have using the proper channels that deposit them into the shredder, and saved the showdown for after Trump won.