Can the cause of this flash arcing be repaired?

My GE Profile 1.5 cu. ft SS Microwave/Convection Wall unit was purchased in 2006 and began flash arcing in 2014. I removed the non-metal plate on the inside right wall and discovered a 'burst' laceration measuring about 1/4" through the underlying metal wall. Obviously unsafe to use, especially leaking radiation.

My question: Can this metal 'burst' laceration be safely repaired by a technician, or is the unit now 'toast', and needs to be replaced?

FYI: I had a second extended warranty through Assurant Solutions but they refused to authorize repair, since the unit still technically 'worked' albeit unsafely. I cancelled the warranty and the M/W remains unused, in place.