2014 Toyota Tundra Catalytic converter failure

sorry for the long post

so back at the end of January, my factory Cat failed, 89k miles. i was driving home and the front weld of the cat busted i was out of warranty so i pulled into a Meineke, they had one for me the next day, (aftermarket). Exactly two weeks later the exact same thing happened. so i thought okay something has to be causing this right? they replaced the Cat and i took it to a Toyota mechanic, could not find anything that could be causing this issue other than my injectors were really clogged so maybe that was the issue, so we had the injectors cleaned and did a complete tune up. Exactly two weeks later the same Cat fails but didn't blow the weld just clogged, the check engine light now comes on for the first time, take back to same toyota mechanic after replacing the Cat, he keeps the truck two weeks driving it almost every day hooked up to a computer, finds nothing wrong, suggest that i put factory cats on. (i probably should have done that to begin with). any way after getting it back it goes out again a week later, i understand that factory Cats are stronger but damn two weeks seem like too short of a time for aftermarket to go out, this time i take it to a a different mechanic and he keeps the truck for over a week and finds nothing, suggest the same thing about factory Cats. well since this was a new Cat i was gonna give it a chance, bad move its out again.

i know that i should have and will put Factory cats on but my concern is that something caused the original cat to blow the weld, and two weeks seems like a really short time for even aftermarkets to go out, and no one can find out way. any thoughts?????????