This HAS to be it. I've been saying since the beginning that this lie was extremely ill-advised, and it doesn't line up with his usual protocol for dealing with damning information getting out, which is to say nothing about it. Just vague dismissals of "troll nonsense". When people saw Champions open on his phone, he didn't claim he got hacked, but for about a year he has stupidly kept going, in detail, about allegedly having thousands of dollars stolen from him.
I don't know how, but Kat had to found out about the bank leaks, it would perfectly explain why Phil keeps this dangerous thread going. Rich was right when he said that Phil could've avoided those leaks happening by jeeping his stupid mouth shut, and now he's inviting even more intense scrutiny by the kinds of people willing to commit unethical acts in order to expose such a scamming liar.
He's taking this risk because it's the knee-jerk lie he told Kat, and the consequences of admitting the truth to her scare him more than anything else does.