Being in the south you would already have shb in both hives anyway. The only difference is one hive is strong and can keep the beetle population down to a toleerable level and one hive that is weak an unable to control the beetle population and/or the larva population.
I would look throught this hive again and see if the queen is still there. If she is there I'd shake her and the other bees in to a nuk with fresh frames, add a frame of bees, eggs, larva from the strong hive. Take all the old frames and freeze them for 24 hours, then reuse them. With small population hives must be kept in smaller nuks here in the south during the summer months. Splits and summer swarms are risky this time of year due to shb. I have found that combining hives can lead to dead queens as well.
If your hive smell as if it is fermented it may be too late. Good luck with the bugs and keep those hives strong, in the sun and watched over!
If you build it they will comb it.<br />Tim Rolan