You would need cool air blowing to lower the temp, blowing hot air is not going to do anything, if your lucky maybe a degree or 2. Your not giving your snakes an option to regulate its body temp especially when its 90 in there which could be stressful not having the option to get away. Right now I'm having the same problem Its 85 in my house but I haven't put my ac units in my windows yet bc are nights are still in the 30. Ive tired fans doesnt work. Luckily outside is around 65 so I'm able to put a fan in my window to blow the cooler air in and that keeps my cool sides at 82 and hot at 90 sometimes lower but then my rhp kicks on. Does your house have ac? If so I would move them inside and your heat devices will do there jobs. You can keep your humidity up with misters or humidifiers, there are lots of ways to improve humidity. My house humidity is at the lowest 15 and highest 25ish and I have no trouble keeping my humidity at 55-60 and no trouble bumping it up to 70 during shed.