Not going to do a three page reply today, so all y'all can relax.
Kri, I don't know this school, nor any of the trainers, but I took a peek at their 'Trainingsmethoden' - which IMO says all the right things.
I like that they give background info as to why dominance theory is the wrong approach, like that they explain the rationale behind positive training, like that they explain how learning theory works, like that they emphasize building a bond between the dog and owner.
Checks all my boxes so far.
See if you can schedule an observation visit, without your pup, to assess if you feel the chemistry is right.