I got it backwards because I expected the counterfeit part to use a newer process IC (less silicon area) than a possibly more reliable and perfectly suitable for serial connection speeds 'vintage' process on some long stable spin of silicon.

Why allow for newer processes on the counterfeit? They'd implement it using the least expensive, most mass produced chips possible, which are more likely to be cut from wafers hitting the sweet spot of size / feature and price crossover.

I wanted to try and figure out out before I did that. No dice.

This is how I ID'd it; I have next to zero experience with ICs, but I've opened up a lot of devices for fun or repair and the cheap stuff always has wiring haphazardly contorted like the left side on the counterfeit, like someone had to force it in there and squeeze it shut just to get it out the door.