Had the same thing happen to a Ford 9 inch on my old truck.
It kept leaking around where the tube went in, and I kept taking it back under warranty.
They finally got the leak stopped, and about 2 years later, I was under checking on things and saw where the tube had slid out about two inches, taking all the black silicone rubber they had put on it with it!!
I jacked it up on the chunk, put a big block of wood on the center of the axle, and whammed it with a big sledge until it went back in.
Then drove carefully and nervously to a friend's welding shop.
We pulled the axles and chunk, ground off all the old weld after marking the tube and chunk using the old weld marks to be sure.
He rewelded it, plus welded a 3/4 inch thick plate on the bottom of the housing. Ground the edges tapered so they would not hang up on stumps, and then drilled and tapped a hole up through the bottom.
Put an Allen head recessed plug in, and put it all back together.
Wound up with a good rear end, plus a drain plug for changing the grease like I do every year.