we had a look on the photos and it seems, that some issues happened during installation the flange and gear box unit.
Find a small pdf-file with some notes, how the installation of this unit should be.
I heard from our mechanic Markus Trunzer, that when he arrived at the plant this and other gear-box units were installed from J&J personnel. Steffen Wendt told you, that you could wait until Markus Trunzer will arrive and he should mount this unit.
He only check with the spirit level, if the unit is installed correctly but not if it is built braced.
One picture shows the break on the shaft and it seems, that this shaft had an old fine crack (black color on the crack zone).