What brand is that riser? I've been burned twice by no name ones off Amazon that worked for like 3 months then started throwing errors. Also how are your temps in that Dell case with the 3080?

Scrap happens in every shop and that 0.040 miss on a back jaw is a pretty normal mistake for a green operator, not some huge disaster. In my experience most stock that comes in is oversized enough that you can just face off the extra and rerun the parts, so you're not really eating a whole bar unless the print has a tight overall length callout. Checking with an indicator on the face is fine but it adds time to every setup and setups are where you make your money, so there's a tradeoff there. Your mileage may vary by material and part cost, but on cheap aluminum slugs I'd rather teach one guy to eyeball the face and check the first part than slow down every job with a touch off ritual. Take this with a grain of salt since every shop runs different tolerances, but the real fix is usually having the operator measure the first one and sign off, not adding steps to the setup.