2008 Tundra transmission corners busted off where the bolt holds on for the Pan

I Was replacing a solenoid inside my transmission and I had to drop the pan to get to it. 5 out of the 12 bolts snapped off which I was prepared to replace after reading a lot of forums saying that would happen so I bought extra bolts. The crazy part is that one of those snapped off bolts was in the corner and I used my extractor to pull it out when the corner came out with it too!!! . I couldn't believe the corner would just pop off like that with it. So my question is... is it possible to just weld it back and it's also aluminum or just leave that corner be and just have 11 out of the 12 with no leaks hopefully? I have a picture.

 

Many cast alum structures have an unweldable alloy. Even if it doesn’t, castings are dirty and very difficult to get clean enough to weld. This would seem to be very difficult to do with the trans installed.

I broke a bit off in one of the bolts trying to get it out. As you may know this is almost impossible to get out without destroying the original thread and kill my chances at getting a heli coil in there. Ended up making a brace from 1/8 angle that bridged across two good bolts and used another bolt in the center to apply pressure where the missing bolt is.