The idea that it's "hard to find a good notary" is kinda overblown. A notary isn't some skilled trade where quality varies, they just watch you sign and stamp the paper, that's it. Banks being booked two weeks out isn't a notary shortage, it's just banks not caring about a free service that makes them no money. The UPS store thing makes sense too, they're a shipping business first, so why tie up an employee for four bucks when they could be packing boxes. You solved it yourself with the $10 shop, which is honestly the normal price everywhere, so it sounds less like a crisis and more like you just didn't know where to look.

That dust packed in the lock is the real killer here. I bet what happened is the cam or the lock screw wasn't biting all the way because the crud was acting like a cushion, so you torqued it down and it felt tight, but under the vibration of a long rip it just walked. Denver's dry air doesn't help either, that white oak is probably moving as you cut, which adds side pressure the fence was never really fighting before. Taking it apart and cleaning it was the right call, but now you know that's a yearly job on that saw, not a one time fix. If you keep the same fence, hit the lock mechanism with dry lube instead of oil so dust doesn't cake back in.