Yes, if it is so, but maybe it's not always so? Everyone has their priorities, mine is checking queen laying time and pattern. Sounds to me like your priority is more for honey production, so in that case, I might do just as you say, kill the 'chances are good' old queen and join back to original hive and add supers. I'm sure many people have done just that, many times in the past.... But it is my understanding that the old queen leaves with the swarm if this is so than she is with the swarm I caught right?