Filter data query from another data query result

Here is my problem for today.
I have a query which returns Groups (which has a trainers ID)
I would like the next query to Filter Trainers (but leave out the ones already in the group)

Can not get this to work with anything I am trying.
Any ideas?
Heres a link to a test page

In your query2 use NOT IN and then use this as a value:

{{query1.join(",", "trainer_id").split(",")}}

Just replace trainer_id with your actual column name.