Three days for a colon though? That seems like a bit much even for a rookie mistake. Most people would just google the error message and figure it out way faster than that. Not trying to be a jerk but maybe the real lesson here is learn to read your error messages instead of reinstalling Windows.

11.8 volts at the battery with the engine off doesn't really tell you much about the alternator, that's just normal-ish resting voltage for a weak-ish battery. A better test would've been checking voltage while it was running, should be 13.5 to 14.5 if the alt is charging. The bearings being toast at 98k makes sense and you prob saved a bunch doing it yourself, but just because the shop agreed with you doesn't mean the tow guy was flat out scamming. Those dudes carry batteries on the truck and get a cut, sure, but a dead car at 11pm in the rain often does just need a battery or a jump. You already had a multimeter and knew what you were doing, most people calling a tow at that hour don't, so he's prob used to pitching the easy fix first. Not saying he was right, just that it might be less of a scam and more of him guessing at what usually works.