You are right, I also can't trust Ten Hag. Last season was not good for Leverkusen, they couldn't even compete with Bayern Munich for the title. I even have doubts about the upcoming season. Ten Hag doesn't have much of a reputation and he doesn't have much of a track record. Last season he was linked with Manchester United where his performance was not good at all and he was putting Manchester United in a bad situation. Now it remains to be seen how he will do with Leverkusen, but I don't think Leverkusen will be able to do anything good in the upcoming season.
I was not expecting anyone that understand what soccer is to trust Eric Ten hag after everything he did last season when he was with Manchester United, the season has started am waiting to see if he can do it right this time, talking about reputable that's zero if am allowed to judge, that guy is not a good manager, you will agree with me that Manchester United gave him much time to improve but the ran out patient because it was as if nothing is going to change, the more the buy more time for him, the worst the team becomes, i don't expect anything different from him now that he is in Leverkusen unless the available players will take the cross to improve their performance to enable them contend very well for their league title.