Seems like the new 3.13.1 Firmware for the Prusa MK3S and the 3.0.0 Firmware for MMU2s destroyed my printer.

After downgrading because the firmware does not home the mmu idler properly I have the issue that X axis won't home properly too.

5 years without major errors and with astonishingly just a handful of failed print came to an end I think.

Contacted prusa support and they think it is a problem with the cable guiding from the extruder assembly though I assured them that it is fine - just as it was before the not working software update and exactly as it is on the other printer that just works fine and did not receive the update yet.