Can you weld die cast? I can see how the inner housing "popped" out given the inner housing is bolted to the body brackets and effectively wants to pull itself away from the outer housing. So gluing the inner to the outer housing was never going to be an effective method of manufacture. Rivetting the inner and outer housings together or the judicious placement of a few small screws/bolts may well be the only effective fix. I'm sure you'll beat it, whichever fix you choose.