The chicken breeds that you have should be able to handle the coming cold temps.. The one molting would be only one questionable. All depends how severe the molt is at this time.
I don't know how your coops are set up. The size of them is also a factor. If you have small coops,, I understand that you are doing the best you can.
Here is something for your consideration for the future,,
If your coop is sufficiently large enough, all your chickens should be able to stay in one coop. If the run space is also large enough,, the chickens usually will not be bothered by other chickens being there.
It is in the run while outside, that integration is best accomplished. If chickens are always separated,,, then they do not integrate.
So now lets get to your problem that is current. Try to block off any draft winds from blowing thru the coop, roost area.
You do need to provide ventilation though. The ventilation should be openings well above chickens' heads as they sleep on roost.
A draft,,, is when the air movement is sufficient to ruffle chickens feathers.
Ventilation,,, is when there is gentle air movement thru coop to carry away moisture, and Ammonia buildup.
For water,, consider getting Heated dog water bowls. That is what I have in my run currently.
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There are other ways to provide liquid water options,,, but you are somewhat pressed for time at this moment.
I know money does not grow on trees,,, so consider visiting some thrift stores, if that is an option. I got mine used for under $5 each. The one pictured above is going for $44 at Walmart.
Lets see what other people suggest.
WISHING YOU BEST,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,and