Parking Assist: Adjust Blind Spot Zone

The Caddy, which is now equipped with a wheelchair ramp, has its two middle ultrasonic sensors moved back approximately 7 cm due to the rear opening. Now, it constantly beeps when the wheelchair is being loaded, and the area of the middle sensors is fully marked on the RNS510 with the optical parking system.
Workshop solution: The sensors were rotated. However, this didn't work either, as the floor was recognized as an obstacle even with the slightest imperfection. This was then reverted.

Interestingly, when using VCDS to check the parking assist system, the control unit (STG) only displays a very short value (20) for the range of the middle left sensor, while all other sensors show a value of (255). If you lift your hand about 2cm away from the right edge of the bumper, VCDS also shows a small value for the middle right sensor. I suspect the mounting positions are different here. The cable length prevents any twisting or swapping of the wires.

The "Adjust Blind Spot Monitoring" function is not working. It sometimes displays 0 and sometimes 10, which, according to VCDS, would be the value for the installed blind spot monitoring system.

It's likely that coding the CAN gateway or parking assist features on an AHK (Aftermarket Head Unit) won't be possible without the AHK itself.

[Translating...]

Autoscan?

Damn! The error keeps happening. It looks like a new sensor will be necessary for now.
Unfortunately, the sequential actuator diagnosis is not yielding any results.

So, primarily, it's a sensor malfunction...

Despite this, doubts arise in my mind.
Since the ultrasonic sensors themselves have the same part number, I'm simply going to have the middle sensors swapped with each other and see what happens.
Too bad the self-test isn't working.

Yesterday, an inspection was carried out. I thought they would at least read the error codes and discuss the next steps with me.
Denkste! No interest! / I don't care! / Not interested!
I'm at a loss. If there really isn't a solution for this, is there a way to disable the parking assist feature?

I don't quite understand the problem. Could you please take some photos of the modifications? And where were the misaligned US sensors reinstalled? Also, when was/will be something displayed as a distance?

Here's an example of what it looks like: