I have previously read back to the beginnings of your woes.
Yes, both small colonies can develop, but there is a big BUT.
You are clearly inexperienced and are lucky to have actually got a queen from the original disaster.
Had you done the wrong thing early on could easily have finished with a queenless nuc.
You now need to read up on how best to treat very small colonies, as your inital treatment of the colony was, to say the least, lacking in thought and previous reading around the subject.
There are some who advocate just throwing a nuc into a cavernous space and leaving them to get on with it, but there are far better ways and practices for the one, or two, hive owners.
Your problem is now compounded in that the bees are dwindling and have been split in half from the original. Not as bad as it may appear initially (there was emerging brood) but the principle still applies.
The weather may have been more in your favour (warm, if still very wet) early in the month, and August should have better weather (fingers crossed again!!)
As I said earlier, live in hope but be prepared for the worst. You have used up some of the cat's supposed nine lives.
As I see it now, your likely biggest problem will be wasps - but their activity seems to be a little depressed to say the least, this year.
Take on board that you want more bees, not necessarily more stores, and treat appropriately.
That means warmth, minimum space that they can be working and brooding, no feeding unless they actually need it, no gaping holes in the coverboard and a small defendable entrance.
Be prepared to unite if the wasps arrive, or you could finish up losing both small colonies.
They will dwindle for the next three weeks and then, depending on numbers and conditions they may start to expand quite quickly. Good luck. You will need it.
M100 was closest to the mark a couple of weeks ago, but I missed that.
RAB
PS. Feel free to PM me if you want some uncluttered, honest and reliable advice off the forum, where 'conflicting advice is often rife'.