It reminds me of the start of "Brazil", bugs and all.

Sounds like a plot for a really decent sci-fi book with an AI as the antagonist.

In his current situation, if he zones out, he produces nothing. In the situation where he's aided by the potentially faulty described system, if he zones out, he produces erroneously transcribed data.

Manual verification is likely just as tedious as doing it by hand in the first place.

I've done something similar, automating a similar process. Essentially the screen was split on half. The left was the actual image, the right was the data of what the program thinks it is after OCR and some magic interpretation. The user can scroll around and both panes would move together. User clicks accepts on each value. Otherwise user can edit each value, or add a new value (if it was completely missed) and then accept. Once everything is accepted they can save the data.

On paper it saved a lot of man hours but it was never fully rolled out. The project didn't have a long lifespan and we had enough people sitting around doing nothing to just manually do all the work. But I got a nice award for it LOL.

This is more like some guy in the early 1900s having the job of hand-delivering important information on a horse.

Then deciding on his own on the advice of HN that he should try a car for that task instead, the car breaking down, and the guy getting fired because his employer never approved of this whole "car" thing and he shouldn't have introduced that into his job workflow without having talked to his employer about it.