Re: Dying hive
What I would do is shake the frames off out on the ground, and then freeze them for a couple days to kill any pests off. If the other hive is strong enough, I'd give them some, and store the rest in sealed garbage bags with some moth balls in it until spring. Then air them out for a week before re-using again with spring splits or packages. If you have room, keep them in the freezer until needed in spring. There's several options.
20+ years, raise my own queens, feed when needed, I treat but have not perfected varroa management yet.