Re: Two hives one queen?
Most of what Scuba says I agree w/, but adding a queen will prove unsatisfactory. The colony will likely not accept her even though they don't have one. Best of luck, but it will probably be money wasted.
I don't know how you would go about combining two TBHs, but were they Langstroth Hives, that is what I would recommend. But it isn't the case, so others will have to advise you there.
"Most of my exercise comes from wrestling with pigs and beating dead horses."