If you have the heat coming out but not the air volume it might be an issue with the fan on the heat exchanger. Or it could just be a perception. Try sticking a thermometer where the vent is and see what temp it's putting out. If you're not getting good heat output or the fan is dying there's probably not much you can do about this weekend. So close all the curtains and maybe hang some blankets over the windows. If you have power you might consider getting a small electric heater. However if you do that run another cord in from the 20 amp outlet on the pedestal to run the heater. (be sure the cord is big enough to handle the load) I managed to burn out an inverter running electric heaters off the internal plugs. Come Tuesday give the folks at Rixen Enterprises a call (their number should be on the silver electronic control box) or try
https://www.rixens.com/. Stay toasty and enjoy jellystone. PS. you have help validate and observation I've had over the last 9 yrs of RVing. If you're going to breakdown it will be a long way from competent help on a Friday and usually on a 3 day weekend. Good Luck and enjoy jellystone and stay toasty. ps if you have a spare nozzle you might want to install that and see if it helps.