If it was really a power supply issue, as in either a faulty one or noise from the house powerlines, why am I am able to reproduce the issue (blank images) with a completely different style of power supply in a different country?

Sorry, I misunderstood then. I thought after you got the camera back it was working, but when you plugged it in at your observatory it was showing the funny stripes.
Obviously, if you had the same behavior with a different power supply back home, then that grandiose hypothesis goes out the window.

I sent the camera to Atik recently, they ran some intensive tests and concluded that there is nothing wrong with it so they sent it back.
I tried it at home in the UK on my Mac laptop: all working fine.
I arrived at my observatory in Germany a coupe of days ago, plugged it in and it worked fine.
I wait for a clear night and BOOM it does not work.

This must be the first star shy camera ever !!!

Just a though, maybe try a different USB cable. They are not all made equal afterall.

Reading about these strange behaviors that you have with your camera I would also recommend you to try another USB cable.
See a topic that I opened after struggling with strange and not reproducible problems with my camera ( Thread ).
I could get rid of the problem with a new USB cable. I don't want to do marketing for the brand of this USB cables but they are outstanding, already when you plug the cable you can feel that they are much more solid and my camera now works reliable and without problems.

If we look at the data that Gonzo has provided it shows that the system has connected to the camera and is downloading all the information correctly. It is also able to read images from the camera and display them. That is the sort of thing that involves the USB cable and it all seems OK.

What we see is that the image data that is read from the CCD is incorrect. Sometimes it is blank and sometimes there is partial data - but there is always data. This looks as if the problem is inside the camera, getting data from the CCD. How a USB cable can be involved in this escapes me.

Gonzo, when you get the blank images exactly what does the data look like? Is is always a single value? Or does the histogram show that there is noise in the data? If the data is always one value that may indicate a problem with the ADC but if there's noise then it may be more likely to be between the ADC and the CCD. It's important to know because replacing a circuit board won't help if the problem is actually with the CCD.

I have tried that multiple times already, it's true that all USB cables are not made the same...

I'll Google that USB brand, thanks for the link to your thread, appreciated.

From what I remember from my conversation with Andrew from Atik, the blank image indicates that no data has been sent from the camera (or something like this).
The CCD board can be changed, not that expensive, however the CCD is....

I agree with Chris, the results you posted indicate a problem within the camera. It is clear to me that this is not an Indi/Ekos related issue.

I am coming back to my earlier comment, in which I indicated that the camera is clearly a

Is it really worth spending this much time and energy on an outdated 1.4 MP camera?
Is it really worth even replacing the control board (if that is even the problem) considering the current value of the klunker?
I mean, astrophotography is all about tinkering and solving problems, but where do we draw the line?
My suggestion would be to give it to your son, grandson, nephew, .... for his birthday together with a soldering iron and tell him to fix it.
Thanks to the laws of quantum mechanics, there is a finite chance that he will be successful.

Changing the camera for a Zwo (as an example) would require a lot of work.
Zwo's are USB3 which I do not have on my setup
Any other cameras will have a different backfocus and would require me to review the accessories between the CCD sensor and the flattener...

As much as I agree that it is an ancient camera, the costs of changing it is much greater that you think, in my situation.
I will take it back home, have a think about it and take action.