Actually, with Zenimax talking about him taking actual data from Zenimax servers, you're right. This isn't about a contract dispute. It's about corporate espionage and theft, which is actually a much harder fight to win if you're just pissed off at an ex-employee. And if he took a single file from Zenimax-owned hardware, or a single piece of paper from his desk and his contract did not *specifically* say "You can take any IP regarding VR with you." he's committed IP theft. The only question is to what degree, and Zenimax seems to think that it was important enough to be worth the whole company (at least, before the inevitable negotiation for a settlement).
But interestingly, Zenimax doesn't seem to be positioning themselves for a quick settlement. They're aiming very, very high. This isn't true patent troll behavior, it's not even jilted lover behavior. This is "We got fucking robbed." behavior. They claim they have evidence that he took files on his way out the door, and then tried to cover it up by destroying said evidence. This is a very, very ugly accusation to make. It's the kind of thing you hold back in reserve in order to try and push for a settlement if you're willing to accept STFU money. They didn't hold back.