Okta SCIM with group custom attributes

After I enabled the feature called Group Profiles for Universal Directory an Okta Group Profile was added to the profile editor, to which I added some new attributes (email, externalId). However, after I create new groups with these new properties, and use Push Groups, Okta does not send a POST request to our SCIM server anymore. The error is also not specified. After I remove the custom attributes, the groups are sent again.

It is also not clear to me how to differentiate our SCIM app attributes for users vs for groups. I would need to get the Okta id (similar to the external_id we get for Users) with Groups as well (sent on the POST /Groups when a group is created. for example). However, in the attribute mappings I only see “From Okta user to My app”, where I can choose user.smth and not group.smth.

Any help is very much appreciated!

UPDATE: The groups are not pushed if the custom attributes I add are marked as Required and even if I assign them a value. But if I don’t mark them as Required, groups are pushed, but without the custom attributes I added for them. The only information I get is displayName and members.
{"schemas":["urn:ietf:params:scim:schemas:core:2.0:Group"],"displayName":"name of group","members":[]}