Lacrosse Catalytic Converter Issue
 

I have a 2011 Buick Lacrosse CXL AWD 3.6L. I have a code on for the cats. I changed the O2 censors, tried cataclean 3 times, and some other fuel line cleaners. Check engine light went off for a day or 2 with the cleaners, but came right back like a toxic ex girlfriend. I went to order new cats and I am having the WORST time finding some replacements. I called GM and theyre discontinued, messaged a bunch of people on ebay, Amazon, etc. Found one person who said they would fit, even after giving him vin #, engine code, social security number, etc. Got them, went to put them on.... no fit. I REALLY dont want to have to pay to rebuild the whole exhaust, and dont want to use the universal cats. Has anyone had this same issue and found cats that actually fit the AWD model? Anyy suggestions, or links to buy the correct stuff i need is greatly appreciated. I love this car but I'm starting to understand why the dealer sold it to me so cheap...