Would buy a mated queen if I can find one. This is a V bottom langstroff. We have another that we would put another swarm in if we catch one. Need eggs, queen or cell before we lose the bees to attrition.If it was a swarm, it could have been a secondary swarm with a virgin queen. She would of had to go on her mating flight. Might not of made it back / killed or eaten before making it back. You could purchase a mated queen or try to find someone with a frame of eggs to donate.
Or purchase a nuc and newspaper combine. Several options.