You must deal with the wrong people. I have never had an experience like that. When a repair did not correct the problem or caused another, the problems was professionally corrected promptly.
Both were acclaimed experts in their field. Lots of internet praise, but now when I research the same techs, there are comments about how they are not what they used to be.
Acclaimed Leica tech #1 - sent in my M5 as it needed rf separation repaired. Camera was returned with a rf patch that flared like crazy. Never did it before. Asked the tech about it, she became extremely defensive and denied any knowledge of any rf issues. Also paid her to recalibrate the meter to use modern batteries. Sent camera to DAG who repaired this tech's work. He said the RF condensor was missing which is why it flared. He found a replacement for me. So, what happened to it?... Also he noticed that the meter never was recalibrated, so he fixed that too.
Acclaimed Pentax tech #2 - sent in my LX for CLA. Was ok before, but wanted to give it a one over. Camera was returned with mirror sticking and shutter staying open. Never did that before. I noticed that if I used the MLU it would release the mirror and shutter. Sent camera back - tech first complained that he gave me a great deal on the price! - then I got the camera back a few weeks later saying it was repaired but the MLU was now broken and he didn't have any replacement parts.
So he broke the MLU while fixing the other issues that he created.
So yes, I guess I did deal with the wrong people. But these weren't 'nobodys' but famous techs. I now classify them as has-beens.