Kay Stumper is not that impressive to me, he's not even been able to win over Can Akkuzu this season who's the weakest rookie of the year probably in the TTBL. He has not win over any TOP 50 players in the WTT tournaments as far as I know.
The TTBL teams should invest on the Lebrun Bros. instead. Alexis Lebrun crushed Kay Stumper severely in the WTT Youth's final in Havirov, and he wasn't even playing in the french pro leagues (Nationale 1 at that time with his brother Félix, only the 3rd division).
When Fulda hired Alexandre Cassin, he was the best performer in the french top league Pro A, but Akkuzu was not playing well, and that's why Ochsenhausen did not do a right move here. Fulda did something logical here, they've invested on the right young player who's now ranked 6 on the TTBL player's stats with 16:5, with outstanding wins over Falck, Jorgic or even Kallberg, the best performer again this season.
Stumper (6:2) and Akkuzu (5:2) have nearly the same stats in that player's table.
https://en.ttbl.de/saison/spielerrangliste/
Alexis Lebrun performances in the french Pro A are top notch these months, he has beaten Omar Assar + Cedric Nuytinck on the same championship day last January ! and being only 18.