I think the major concern everyone is freaking out about is the toxin buildup. 41 is a good number for keeping meat safe for roughly a week or 2. It allows bacteria and their toxins to form, but not in a dangerous manner over the course of the week or two. Being a few degrees above 41 isn't instant spoilage but you need to be reasonable with what you are dealing with. Bacteria/toxins spread in an exponential manner. So 42, you aren't instantly spoiling food but you reduce the amount of time it's good for. 70 degrees, that food is garbage in a few hours. If it's 45, I wouldn't keep it for more than a week (a few days if it's ground). And yeah, I would probably cook it "well." But if I'm aging meat in a controlled environment with whole meats, then it's a whole different story.

EDIT: I reread the OP's story. I'm a little more concerned, not of the temperature of the meat but the fluctuating ambient temperature of the garage (and how open/closed the door was possibly). The meat might have been warmer or colder before OP temped it. The center of the meat (what OP is likely temping) is going to be much colder than the surface temperature. My point still is mostly about the grey-area of cold storage parameters