My initial thoughts on PM approach:
- Allow user to request group membership from groups page or individual group page via join button (as currently implemented)
- Send request PM in background
- Change button text for requestor to “Request Pending”
- Exclude requestor from PM (or would need to allow TL0 permission to send; hide PM dialogue)
- Send request PM to all owners
- Include link to an Approval Page in request PM (include all pending requests on page)
- Upon owner action for the request, send welcome/declined PM to requestor and owners (with default PM text for approval PM and for declined PM which can each be customized by sender at time of sending)