One additional idea i have is looking for employee review platforms in other markets.
I think Kununu has mostly reviews out of Germany. Maybe there are reviews on for example Glassdoor from U.S employees or also reviews from employees of other major European markets on other platforms.
Getting a more comprehensive picture of what is going on at Sixt remains a priority.
I am still undecided what to do but reducing the position esp. if we find more worrying signs is certainly an option.
Edit: Depending on our findings, we might need to consider whether Sixt is currently performing worse than previously due to cultural problems and what effect that would have on the valuation model.