96 degrees...is that the ambient temperature, or the hot spot?

If its the ambient temperature, that can be dangerous. If it is 96 on the hot spot, I wouldn't be overly concerned so long as the tubs are large enough that the snake can easily get away from it if they need to. Again, thats higher than what I'd be comfortable with, but I don't think a 96 degree hot spot would be all that harmful in the short-term.

If there's a window in the garage, a window A/C unit would be an easy fix. You could even hook the unit up to a Ranco, set it for cooling mode, and set the temp at 82 to keep the room temp down on hot days.