Administrators are unable to share members' content with a group that the admin is not a part of.

Additional Information

Workaround

The administrator must be a member of the group in order to share the content. From the REST API, an administrator can add and remove their username to enable the ability. Refer to the following links for more information:

https://developers.arcgis.com/rest/users-groups-and-items/remove-users-from-group.htm

https://developers.arcgis.com/rest/users-groups-and-items/add-users-to-group.htm

The ArcGIS REST APIs documentation in the links above specifically states that the administrator has the privilege to change group members.

Steps to Reproduce