It sounds like the queen cells were destroyed by a virgin queen. First the virgin stings them, then the workers tear holes in them and remove the contents and discard it.
If I were you, I'd give the virgin more time to mate and begin laying. If you combine them prematurely with another queenright colony, the virgin may destroy that queen as well.
If I were you, I'd give the virgin more time to mate and begin laying. If you combine them prematurely with another queenright colony, the virgin may destroy that queen as well.