So I'm currently at the dealership and the tech is showing me a copy of the pertinent section of the 2023 owner's manual which, oddly enough, has two more steps than what is shown in my 2023 manual: disconnect the negative battery terminal and close the hood. Thanks a helluva lot, GM. I specifically bought this model because I wasn't going to have to disconnect the battery. That's why I downloaded the 2023 manual and confirmed the procedure before buying it. I'm still going to try the suggestion of removing the fob from the vicinity of the car to see if I can avoid using a settings saver. It also doesn't explain why I was initially able to successfully tow the car around the neighborhood several months ago on a short test tow. Maybe I unknowingly used the suggestion above in that instance.

The tech's explanation for why it worked on the initial short test tow was "You got lucky, the system didn't catch it for some reason." He was dismissive of the remove the fob explanation. Photo shows my manual (which tech said was "generic") and the print out from the specific manual (GM document #6003321).
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