Was not aware of lifter issues at the time?

Bought first truck 2020 Trailboss w 38k miles 9/22 for work and put another 38k by 4/23. So busy didn't think of warranty, wasn't aware of lifter issues at the time. Brought to dealership for squeaky belt for 300.00 all good. I went to pay/pick up and was told mechanic heard knocking when driving out the shop after inspecting found Cam damage 7500.00 to repair and got 10k quote to replace engine which I ended up doing. Inquired about recalled lifters but I didn't qualify for assistance? 4700. Parts with 4600. Labor I guessed, seemed right? Drove truck 3hrs to work ran funny oil light came on and started stalling out made it to Take 5. Mechanic said no oil in engine called dealership said it was "odd" and bring it if. Got oil change. Did not bring in because wasn't sure did not trust them plus need truck for work every day and had been in shop for a month and loaners not available when I asked. Truck has been running decent but noticed on Engine Replacement Receipt Mechanic comment "Engine oil cooler and transmission oil cooler caps missing." I asked the Mechanic and Manager for an explanation over a month ago and still no response.

This could all be normal I don't know.