Are there other witnesses to the porn that have kept their counsel. But they would be scoring political currency and await payback.
And true, the first thing a lawyer would say to him is "how much can you afford to loose"? Forming an unbiased jury would be difficult too. All male? I don't think so.

The real reason he hasn't gone after them may be that he may be in court in a separate issue and the cost of both cases would weigh heavy. The time he would have to spend on both. His standing would drop further. And his friends would tell him he was a liability. He is, but moreso.

And it is not difficult to paint a scenario where the "officers" feel their career was blighted by saying anything at the time. If you were doing your diligent duty and were told you had exceeded your authority (in an attempt at hush-up) - well, put yourself in their shoes. Mind you, I would have listed a sample of URLs and counted the websites and kept the data!

The world and his brother are making a correlation between the porn and the harassment. It is what humans do, we evolved to see patterns, and it has served us well as a species.
By not going to court, the porn is at least unproven. And the other issue? Who's career is it blighting now? Apart from the Demon Green? Or maybe May?
Let's have a list, who's rushing to his defence?