I keep two Yellow Foots (I understand they need more humidity than Red-Foots). You sound as if you have done the right things. If you want to give them more humidity – try putting a hide in their enclosure (Micro environment for your red foots to enter). I personally do not have a hide – but do mist my tortoises every time I pass them.

About your sexing – I believe it is hard to determine the sex of your Red Foots until they are a little bigger/older. My Yellow Foots are a little larger than your Red Foots – they weigh about a pound and a half each. Anyways I think I have a boy and girl because
- One is rounder and wider than the other
- One bobs it’s head when it comes in contact with the other one or another Tortoise looking animal
I will probably find out in about another 2 or 3 years when they become sexually mature.

About your beardie – They should be fine to bread a low humidity as they come from desert country.

One last thing – air-conditioning takes the humidity out of the air in a big way – so try evaporative air cooling

Good luck with your Red-Foots