I'm only a reluctant amateur photographer, but my understanding is that damaged sensors cannot be repaired, and that manufacturers will quote repair costs totalling or exceeding the cost of an entirely new camera.
Seems it eventually worked for him, after several attempts to adjust the position to get correct focus,
but if you read the comments on the video there are many people who've messed up their camera trying to do this.
They might send that back to the manufacturer to fix.
In the Reddit thread, they talked about replacing the aperture module for some of the lenses; that's just a simple swap, along with cleaning the adjacent elements.
I wish the blog post had talked more about that. I'm curious about their repair process. What capabilities do they have in house? Can they replace a broken sensor?
They blog a lot about their repairs process in general. It's primarily mechanical damage to lenses they appear to normally deal in - the focusing rings, aperture mechanisms or realigning optical elements dislodged by drops and so on. An embedded CCD/CMOS sensor is probably a full logic board replacement I'd assume, as opposed to some kind of sensor only replacement, given it's almost always soldered on.
There are a lot of things that a professional repair shop focused on a particular type of equipment may be able to do that aren't practical for anyone else - including manufacturer repair facilities. Louis Rossman is a bit entertaining on this: https://m.youtube.com/watch?v=ocF_hrr83Oc