I never bothered looking under my truck but my old Jeep Grand Cherokee had vent hoses that were mounted higher up on the frame. Thats where water would get into the diffs.
Ideally, yes, and I was aware, but i wouldn't bank on it or risk it unless your sure...and the clamps holding those hoses on are tight.
I've seen it happen even with the diff vent hoses mounted up higher. Water still got in.
Those trucks also had big lift kits and big tires on them. Much more so than just a leveling kit. You may wind up with water in the cab.
I would not attempt that in my stock height, stock tire 2500, but that's just me.
Could I make it? Probably, but it'd be sketchy and my 2500 is significantly taller than a 1500
Just my thoughts. Please post a video if you go for it. Good luck.