meatballs refrozen, safe to eat
The vegetables might be fine, since vegetables can be stored in the fridge for up to a few weeks, depending on the kind. The meat should be thrown out. If you don't know at what temperature it has been kept, and for how long, there is no way to tell if it is still safe, and food poisoning is unpleasant. I would throw everything out, but I strongly recommend at least all the meat.