Does anyone of you know of cases where Google blocked people/ locked the accounts of/ otherwise punish people using ad blockers? (I'm asking for the book I'm writing.)

Not that I have heard of.

And if they did, I'd be devastated. Ads are now being blocked by my company's firewall, which I have no control over, so it would be a right kick in the balls if they disabled my account because of my company's actions!

Nope, and I have been using AdBlocker+ for ages.

I've had AdBlock Plus installed for as long as I can remember, and I've never had issues. In fact, many of Google's pages are in my whitelist because they don't have ads on them. (Places like Reader, etc.)