What's wrong with keeping frozen vegetables in refrigerator?
After a few days, they're almost certainly still safe. Most fresh vegetables will last a few days to a week in the refrigerator.

The quality might not be amazing, though. Frozen vegetables tend to get limp and soggy when they thaw; after a few days of being in the refrigerator, they might very well turn to mush once you cook them. But the chances of food poisoning are remote.