Wanted to post an update to this. I tried the JB weld approach, tried to save the drain. I wrapped the original plug in teflon tape, put JB weld on the broken pieces and assembled everything as it should go. I also built up some JB weld on the outside of the drain for reinforcement. I let it cure for a week.

The end result was that it didn't hold. Not sure what happened, everything was clean and shiny. I used brake cleaner and acetone and everything was dry when i started.

On to plan B, this is where I have to give yet another huge thanks to John and Simon, in case i didn't thank them enough yesterday

John brought a trailer over and after a hell of a time trying to find ramps we finally got it loaded up and took it to Simon's friend (Scott, who's an awesome welder and while not on rennlist, should he ever come across this - huge thanks) who lives about an hour away.

We spent all evening trying to get the drain hole welded shut, it was definitely an endeavor. Finally everything was sealed up, pressure tested and I got to drive it back home. Everything went great - no issues, it was essentially my first real drive, and lots of fun (minus the 45 min in stop and go traffic on 635).

Huge huge thanks to you guys, you made that drive possible.

Later that night when I moved my truck from the front of house to the back, I noticed a black dryer looking hose in the alley that looked very familiar. Checked the 928, sure enough lost the alternator cooling hose (which i had just replaced with the gates hose), luckily the sensor is still intact. Not sure how that happened, but if something had to to go wrong, and that was it, i'll take it

I've attached the pic of the weld and a pic of the hose.

 

Nice weld job.

You might post a picture of how that hose was routed,

from the looks of it it was rubbing on the ground for a bit before it fell off .
the hose should go through the lower towhook anchor between the frame and hook,
my guess is that it was routed under the hook thus closer to the ground.
Maybe the ramps helped to loosen the hose

 

I routed it through the tow hook like in the attached picture, but perhaps I did leave it too long and it dragged on the ground until it broke off. Although when I installed it there didn't seem to be much slack to make that possible.

I also have the front spoiler off (which was prob a good thing for putting it on the trailer) when i put the spoiler back I'm thinking that should keep this from happening again.