I have a 2011 365BHS... one mod I made to help with the bunkhouse AC was to install a 24x10 white vent grill above the main door to the bunkhouse on both sides of the wall. It's a simple mod - you don't have to cut the one 2x2 stud that is centered above the door. Just cut the openings along each side of it.
Here is a link to the vent grill I used: WHITE VENT GRILL
This allows the hot air to vent to the main area as it rises in the bunkhouse area.
It's not a 100% cure all ---- but it did make a noticeable difference. I may add another vent in the wall above the bunkhouse/bathroom door....