Mean bees sometimes equates into queens that are very good at hiding. If you can get a couple other beekeepers to give you a hand that may help.
Other than that, break apart the brood chamber into separate hives. Wait a few day, and look to see where the eggs are, where the queen cells are, etc. But do not stop at just finding a queen in the first box. There is always a chance you may have more than one queen.
Some isolate the queen with excluders, but putting all that back together to deal with a full size hive again another day, just makes no sense to me.
Once you break the hive brood boxes apart into individual boxes, you can go through one or all, and take your time without being overwhelmed.