How can we reduce humidity but keep the temps up until the lighting issue is resolved? Our imaginations have expired....and we fear our girls may follow suit if we can't rectify the situation immediately.
Lol! I love the way you've stated your problem.
It's always difficult to troubleshoot someone's problem without knowing their full situation... however...

How cold does it get outside the tent at night?
My girls get down into the mid to upper 60's and it didn't seem to hurt them a bit.

What are the humidity levels outside the tent?
Can you open the tent up at night and let the humidity out?