OSIAM Dataset 'Problem with "not"-Filter'

1_create_data.sql

-- users
INSERT INTO scim_id (internal_id, id) VALUES (1, '07486cd7-f3f9-4b4f-8379-371bc10fd412');
INSERT INTO scim_id (internal_id, id) VALUES (2, '704cf301-264c-4caa-aced-8873bb1cbf48');
INSERT INTO scim_id (internal_id, id) VALUES (3, 'c18a780b-d858-4177-80ef-5de9491eee2c');

INSERT INTO scim_user (internal_id, user_name, password) VALUES (1, '1', 'o5pMnVkU');
INSERT INTO scim_user (internal_id, user_name, password) VALUES (2, '2', 'QjK8kgyR');
INSERT INTO scim_user (internal_id, user_name, password) VALUES (3, '3', 'i43FXsmF');

-- groups
INSERT INTO scim_id (internal_id, id) VALUES (4, '6f846c19-05b2-434a-9877-ce6a15dd80b3');
INSERT INTO scim_id (internal_id, id) VALUES (5, '338635f5-fa6e-422a-8db8-b212408b3563');
INSERT INTO scim_id (internal_id, id) VALUES (6, '39ce98ed-c3f8-460b-a0f8-f7af8b4544f8');

INSERT INTO scim_group (internal_id, display_name) VALUES (4, 'A');
INSERT INTO scim_group (internal_id, display_name) VALUES (5, 'B');
INSERT INTO scim_group (internal_id, display_name) VALUES (6, 'C');

-- user-group mapping
INSERT INTO scim_group_members (members, groups) VALUES (1, 4);
INSERT INTO scim_group_members (members, groups) VALUES (1, 5);
INSERT INTO scim_group_members (members, groups) VALUES (1, 6);
INSERT INTO scim_group_members (members, groups) VALUES (2, 5);
INSERT INTO scim_group_members (members, groups) VALUES (3, 4);
INSERT INTO scim_group_members (members, groups) VALUES (3, 6);

2_query.sql

SELECT DISTINCT members FROM scim_group_members
JOIN scim_user on scim_user.internal_id = scim_group_members.members
JOIN scim_group on scim_group.internal_id = scim_group_members.groups
WHERE members NOT IN (
  SELECT DISTINCT members FROM scim_group_members
  WHERE groups = 5
);