I'm sorry to hear this happened to your wife. I think that was a big mistake to resign though, she pretty much willingly forfeited any legal recourse. The best thing to do for anyone in these situations is to make no official statement at all regarding vaxx status if questioned. If terminated for failure to disclose your status, immediately file suit for the dozens upon dozens of OSHA violations they have just committed. You're now in the territory of seeking damages.

But you must make them terminate you solely for vaxx reasons. Anyone quitting beforehand pretty much tossed their employment in the trash bin for no good reason. Many companies are hesitating on any official inquires into vaxx status, and are even more hesitant to terminate on the issue. Most of the firings so far have been government positions and hospital workers. We still haven't seen most private corporations bite on the issue yet because they know better than anyone how wide open they'll be for OSHA violations. They don't want that smoke.