Lost last response? Got under today with a flashlight (2552) . There is a black vent tube in the bath room closet, drivers side, that runs up thru the roof. PC drilled an ample hole for this pipe to pass. Lots of room for critters to pass. Would like to foam close from underneath but can’t get to them because of position of black tank. Checked under beds and all cabinet and couldn’t find any evidence of housekeeping. Will try packing some pink fiberglass insulation around the gaps where the black pipe passes thru.