How far away is the nearest ceiling vent fan? If you pull the bezel for any ceiling fan (just remove the four screws and pull it down gently) you can get access to the interior of the ceiling and if you are within a few feet, you can move insulation aside temporarily to allow airflow into an area.
Recently my middle AC gasket leaked and it came out of the vent about two feet away. By pulling the vent bezel I could reach all the way to the ducting where it was dripping out by following the damp insulation "path." I toweled it a bit, then just left that bezel off and in two days everything in the area was dry as a bone. Pulled the insulation back into place, replaced the bezel and all is fine.
One disclosure...I have long arms....37" sleeve measurement on dress shirts.