we once had a mouse in our house hot air vents somewhere. Called around to see what someone could do. Best advice we got from one furnace company was:
since we both worked and it was fall they said when you leave in the morning, crack the windows, turn the furnace to around 80F and let it run all day. that will desicate the mouse and get rid of the smell.
Tried that, came home in the evening, problem solved. You might give that a try in the trailer.
BTW on our trailer the el chepo ducting restricted airflow so I dropped the corplast and replaced the ducting with the rigid snap together pipes and appropriate angle fittings. made a huge difference.
2011 Keystone Outback 295RE
2004 14' bikehauler with full living quarters
2015.5 Denali 4x4 CC/SB Duramax/Allison
2004.5 Silverado 4x4 CC/SB Duramax/Allison passed on to our Son!