I would bypass the whole "one frame" at a time thing, and swap locations of the hives. This will boost the weak hive and hopefully put to rest this wax moth problem once and for all. She could be a bad queen as we all get one now and then. But the wax moth situation, may be causing the bees to spend far too much energy and resources in trying to keep up with the damage they are causing.
Forget the honey crop. It's either going to be there or it's not.
If you put in a new queen, figure a few days for her to get out and start laying, and another 21 days for her eggs to become bees.
The number of bees are going to be influenced by not just time, but the bees ability to feed and care for the brood, how many they can keep warm at night, how many cells are ready for the queen to lay in, and other factors.
To be fair to the new queen, I would boost the numbers up by swapping locations with the other hive and get them over the hump once and for all. This increase in bees will allow them to deal with the wax moths, allow them to raise more brood, and do what they need too. Anything less and it will just continue to fester and drag out.