In either language they write, that English is mandatory and German is nice, but not requirerd.
Check for the comparably low requirements for a "world wide operator", concerning experience, licenses, languages and more.
It seems to me, that initially they try to collect a bunch of thousands of applicants, many of them from Eastern Europe (Leipzig is closer to Prague and Warsaw than to Amsterdam, London and Paris) and upon that setting up the T&Cs, probably being the worst we can expect, moreover being individually tuned.
The more media talk about a pilot shortage, the more there will be a flood of pilots from every corner of Europe and the world, desperately seeking for better work conditions. Adding those, who desperately want to return from the Middle East, this airline won´t be able to cope with the number of applicants, it receives in the next weeks.