Complex Filter Criteria no Results
The problem of my above question is a core bug. I added it to the Drupal Core issues, hope it will be solved soon. https://www.drupal.org/project/drupal/issues/2935113

In the mean time I found a work around. I use two different filters in the two added groups. Both filter on the same thing.

So in group 2, I filter on my Wat? field.

In group 3, I filter with the 'Has taxonomy filter'.

Both filter on the same taxonomy term but because they are different filters it does work now.