2007 LQ4 Vortec 6000 Gen 3, busted

I bought a box truck for about $1K, put another ~$2K in repairs to cats, exhaust repairs, fuse box, battery, spark plugs, oil changes, & a bushing. Changed the oil once more myself after I changed the spark plugs. Car ran decent except the battery terminals needed replacing, and I wanted a professional once over before my wife started using it. Noisy, but no knocks.

I left the truck with the mechanic. Upon speaking with the technician he sounded very nervous, but I dismissed it. Hey gave the report that they heard a small tap in one of the cylinders, oil pan leak, and recommended we not proceed with the oil & trans flushes the front desk recommended… This engine has gunk all over it, and around 300K on it. I had turned down the trans flush & oil flush, instead asking for a full service oil change (which I understand includes a pan drop), the leak fixed, breaks checked, and the bushing work.

Driving home with the vehicle it died 3 times, they had not fueled. Got it home and tried to start it in the driveway the next day, I saw smoke rise from the starter. I called the shop and asked thenm to send someone to look at the starter, which they said they would replace (I found it to be misaligned or something, clean metal visible at installation edge). The tech arrived and never looked at the starter, instead immediately went to the main gear and tried to turn it, deeming the engine seized. The front desk called and told me the same. I told them I’d get a second opinion and get back to them.

I figured this might be a slipped rod bearing, so I drained the oil (kept by itself for later measure) and dropped the oil pan. I’ve literally found hunks of piston everywhere.

With the work I had done, a) wouldn’t the tech have noticed something about this? B) I need to be sure he filled it with the enough oil, but what other bone head moves would have caused this?