Very little chance the hive can be saved with that few bees. If you had another hive to add them too, that would be a good idea. But I'm guessing you don't.
And yes, putting the queen with another swarm would be fine. But how will you find a swarm just instantly? You need to find it right away. The queen needs care - royal jelly and all. But if you find a swarm ASAP, you could add the few bees AND the queen to that (newspaper method).