Review on 🔧 Authentic GM 12571609 Engine Valve Lifter by Shawn Pollock

I just rebuilt the top of the engine on my 5.3L Suburban from a 2007 AFM. I bought this VLOM as a recommended elevator replacement. The top of my engine wasn't too bad, I had just collapsed an AFM lifter, but while I was taking it apart it made sense to work on the cylinder heads. My mechanic (who is also a relative) and I only put it back together because of a misfire. We spoke to a local Chevy supplier and service technician, as well as several other shops. We checked all possible problems to fix the misfires. Everything points to this new VLOM that has driven ZERO miles before misfiring. Today we take it out to test and re-verify the VLOM. What do I need for a replacement or refund if this part is actually defective?