You want a hot take?
Julian was running a very obvious espionage outfit. Julian didn't want to end up on someone's chopping block. Julian called to get inside track to save his ass, personally, because his former employee got a hold of some very highly incriminating evidence (child porn type stuff) and was going to drop it all, unfiltered, so everyone would know exactly how things were being ran in the world. Remember when there was a coverup of child porn at the state dept.? Well, there ya have it. Julian was trying to sound the alarm to anyone at the State Dept. to let them know "HEY… It's not us, it's this rogue dude that no longer works for us."
Dude on the phone knew exactly what Assange was talking about, likely because he knew what this meant for the State Department at the time. Lots of people would have been taken down in this. They managed to get it under control quickly, and pinned it on a few people with a quick MSM blurb that wrapped it all up nicely in a "Well, we caught 'em!".
Ask yourself a simple question. Why would Assange even care to warn these evil fucks that they were about to get blindsided? Anons should know, by now, that in those cables there were going to be tons of people caught up in Epstein-like shit all over the globe. What else you think the State dept. was really doing besides "foreign relations"?
Assange is in a Class-A prison to keep his ass alive until it's time to drag him out for a full confession of everything.