IIRC ... and it's been several decades since I looked at THIS particular UL standard .... well, I don't recall there beiny ANY evaluation of your making holes. Let me sum up what I recall:
-Boxes had to either be of a certain thickness steel, or be evaluated for equivalent strength;
=They had to pass a modest corrosion test;
-These days, steel requires galvanizing as well as paint;
-Knock-outs, IF provided, were required to leave a hole that was free of sharp edges;
-There had to be a provision for grounding; and,
-Capacity had to be marked.
There were also tests for various environments IF the enclosure was asserted to meet those conditions. "NEMA-1" as simply required to not allow a 1/4" rod to contact live parts.
Now, that's for a simple box. If the box was (for example) for a control cabinet, then another standard entered the evaluation.
I think we place far too much on the shoulders of UL. Device straps line up with box mounting holes not because of any UL requirement, but because the manufacturers choose to design to their own (NEMA) specs. There is NO check on this apart from the manufacturer's desires.
UL is staffed by legions of second-rate engineers who all pretend that they're lawyers. They will never tell you that something is 'good' or 'bad.' The answer to EVERY query is "we can't know without a full evaluation."
Boxes are intended to have holes n them. All the UL tag does is tell you the box is a minimally decent raw material. YOU are the manufacturer, and it's up to YOU to do it right.
Likewise, the "AHJ" is the customer and the inspector - not UL, NEMA, NECA, or anyone else.