Earlier quoted context omitted.
The publication that I linked includes references into the peer-reviewed literature. The author has a PhD in microbiology, and is currently employed as a co-PI at the UC Davis Western Center for Food Safety: https://www.wcfs.ucdavis.edu/linda-j-harris/ So while it's possible that she's mistaken, I think it's much more likely that you are. If you still think it's the former, then I'm open to review any references that…
You and everyone in the food science field can convince me to stop this by providing a peer reviewed article indicating that roasting garlic does not get an internal temp hot enough to kill botulism (I will actually check this next time) and that botulism spores can inhabit the interior of the garlic. I would expect the latter to be false even if the former is true (the surface is the place all of these things grow).…
The caramelized bits of roasted garlic almost certainly reached temperatures far above 121 C. The concern is the minimum temperature though, not just the surface temperature.
I'm not sure how your analogy with chicken is supposed to work. If you cooked chicken, submerged it in oil, and then incubated at room temperature for a few days, then I definitely wouldn't eat that either. The problem isn't the initial population of C. botulinum; it's that they multiply under the anaerobic conditions of the oil.
Likewise, I'm not sure what you think is wrong with their advice on the acidified garlic. The botulism simply won't grow at low pH, no matter how long you wait. The taste and texture will eventually become disgusting, but that's not a safety concern.
You seem to have the idea that cooking fully sterilizes food. That's not correct; it decreases the population of pathogens, but not to zero. So the cooking potentially makes the food safe to consume immediately (since the dose makes the poison, and the dose is very small). But if the food is incubated under conditions where the bacteria can grow, then the dose gets exponentially bigger and the food becomes unsafe. Methods that rely on perfect sterility (like pressure canning) achieve that by applying heat when the food is already in a closed container, and are assumed to lose that sterility once the container is opened.
Water-free garlic in oil should be safe at room temperature, and that publication gives directions for dried garlic in oil. I'd guess that confit would be safe too, and I'm not sure why you think the FDA would forbid it. (Note that it would be safe because of the low water activity, meaning that even if botulism spores are present they can't multiply. It would not be safe because it's "sanitized".)