Well, Nick didn't say Tom told him everything, he just said that Tommy C's characterization of Tom not talking to anyone was not correct, as he said that he and Tom had talked since the allegations.
Nick generally isn't going to platform someone else's story without them saying it elsewhere first, or on live in a conversation, as a matter of self preservation. Off the top of my head this happened during the Mamamax fallout with Nexpo since he was hitting Nick up in DMs to tell him things to attempt to refute max's counter allegations, and he basically had to tell him "look you can hop on the call and talk on stream or you can say it on your socials but I'm not acting as an intermediary".
Tom is his friend but he also can't afford to fuck up dealing with a set of allegations like this, and the safe play is exactly what he did.