Well one things for certain, I sure as hell wouldn't want to be on the opposite side from Google's lawyers, especially when it's something as big as self driving cars, a project they been investing on for almost a decade.

I agree, it looks grim. Actually losing half a billion+, though, depends on some hairball of laws, judges, juristictions, and so forth...around actual damages, punitive measures, forfeiture in a separate criminal case, etc. Handslaps aren't uncommon, and neither are the opposite...awards that seem too large. There's also the degree to which Uber is culpable (provably, legally) vs Levandowski personally.

Would be interested in hearing a prediction from an IP lawyer.

True, but I don't think you need to be an amateur lawyer to deduce that if the company, you just sold, was based on stolen technology then you're screwed legally and financially. And from what we know right now it seems that it was.

I assume opposing counsel has an opinion on how much of the value was based on stolen documents, and how much was not.

I totally get what you're saying. But I mostly don't see verdicts, settlement amounts, forfeitures, and the like following common sense.