We found a solution ... but that's really dirty work on database level. So, handle with care!
We renamed the columns in the database and updated the hybris type definition within the database.
This is the current state of our SQL-Statement:
ALTER TA...
tl;dr ... here is a fix for this problem (I'll explain the reason afterwards):
Insert this into the web.xml of the hmc (usually bin\ext-platform-optional\hmc\web\webroot\WEB-INF\web.xml) after the other listener class:
<listener>
<listener-class>org....