Like he's going to admit that after violating his nondisclosure agreement discussing Q&A at TGIF
and disparaging GCE in public. Of all the things to discuss outside of work, the meeting that starts with a "everything you see, hear, and taste here is confidential as shit, man," slide...
Speaking from (direct personal) experience, someone that malicious needs to be identified quickly and removed, because that's without question not the only thing he's doing due to his disgruntled attitude. Nothing against him, just clearly Google has wronged him in some way and the responsibilities of his legal agreements are no longer important. That means it's time to move on before he harms the company.
Whenever I've spoken about my employment at Google -- even though I was fired inappropriately -- I'm careful not to divulge information that I promised to protect as it's important for my own integrity. And that's even when I have a pretty legitimate gripe with Google. Now that I'm with Apple, a company that ostensibly takes secrecy to an entirely different level than Google, I don't even discuss Apple in public. Ever. I know better.
I'd talk to Global Security about this if I were you since a case could be made that he tried to throw your LDAP under the bus.