Well I believe the front driveshaft comes out of the transfer case to the front axle. That is not the transmission. If has design I believe it does then transfer case is bolted to back of trans. You made it sound like you narrowed down the leak to the trans pan. A leak can also be from somewhere else and blow back on to other surfaces and cause it to look like has a leak where in fact it does not. Best to either completely clean off and wipe down to dry, can use brake clean to clean off with. Or you can add dye to system and look with blacklight for leak. Either scenario will look for leak after drive vehicle. Good luck.