if you have other hives, can't you grab a few frames of bees and brood and add them to the weaker hive? if the frames don't match, you can shake in a few fames of worker/nurse bees. just don't shake in your queen! at the same time, you can swap locations. you may still have drift, but it will help get your numbers up.
I do have other hives but this is my first year, so none are booming. A few have 5 full frames filled out and new bees emerging from their brood (witnessed this and got it on video too during an inspection, it was quite fun to see!). Anyway, I'm a bit concerned about risking those hives to save this one. However, saving this one may be all over. I am not sure what happened but I went out to check on my apiary and things looked normal. I went on a walk through the woods and then came back out by my apiary and there were bees everywhere, and I mean everywhere. You could see them in the air from 150 yards away and I am sure much greater distances (that's how far the woods are from my hives). Anyway, it looked as though bees were going in every direction, but the whole mass certainly created a path to a tree. I ran inside to get the video recorder and got quite a bit of it on tape, have not looked at it yet, I am not sure how well it will turn out. Once I was able to tell which hive things were happening on it seems as though bees were returning to the Italian hive. The Russian hive is now empty. Only the dead bees from the package shake last night remain.
I went out to the tree the path lead to and hear/see nothing. The cloud of bees did seem to end up at the Italian hive, so I am hoping that they simply finished what they started last night and the remaining Russian bees evacuated to the Italian hive. I hope I did not just loose all those bees. I am processing video right now, I'll post a link to any usable segments of the video when it's done.
It sure was exciting seeing this happen, I just wish it was not a problem with my Apiary. Best case would be to see a swarm come into my Apiary and populate an unused hive :-D