sterling, was there only the small amount of capped brood left? Was the old queen still in there? There were no eggs or larvae, just the capped brood?
On the question of colony strength, your advantage is that you have two other packages to draw from. If you have no eggs and larvae now, you could pull a single frame from one colony, then when all that is capped, you could pull a single frame from the other colony. This assumes, of course, that the other two colony's queens laying on more than one frame so their numbers will continue to rotate and grow.
You'll just need to keep an eye on them to make sure they don't continue to make more supersedure cells off the new batch of eggs. They've already got that covered.