I'm new to Hubitat, having it only about a month so far. But I'll take a stab at this.
How about create a variable called AnybodyInBed and set it to false? Then configure your trigger rule to fire with your existing triggers and if AnybodyInBed is False. Toggle the value of the variable to True when either pad activates. As long as one of the pads is activated, the other one leaving shouldn't affect the variable (like if one of you gets up to go to the bathroom). Also, the 2nd pad activation shouldn't retrigger the A/C b/c the variable is already True.