Don’t expect the bees trying to rob your hive to give up in a day, it might take a week or two till they get the message to give up on that idea, as well as possibly a good nectar flow happening. Bees would much rather prefer to forage than fight to the death to rob another hive. It is important in my experience to not allow a hive to become a lot stronger than other hives in an apiary.
Most likely the bees clustering under the hive are your bees and most likely the queen is still in the brood cluster, my thinking is that the hives bee in a robbing situation would be even more protective of the queen and there is no way the colony would let her go out of the hive in that circumstance. Do an inspection when it has calmed down and add a super if the bee numbers are really high needing extra space for bees. Bearding can be caused by a number of issues, internal hive temperature too hot, an overly strong colony for the available space, a honey bound hive are the most likely in my opinion…