When a document is shared to someone outside the group, is there any way for a group owner to be able to see, in aggregate, what content is being shared externally, and to who? We require group owners in private groups to pay attention to who has access to the content, and this seems like it might be a bit of a challenge in Jive 8, at least for groups where this external sharing has been enabled.. We haven't looked extensively at the Jive 8 APIs but if nothing in the Community Manager Reports, I'm wondering if there is support in the APIs and/or reporting database to be able to pull that kind of information.
Also is is possible to enable for the group, but restrict the ability to share externally to Group Administrators?
There is not a supported, out of the box report that will provide the list of users that content has been sent to. The information might be stored in the database, however since this is not supported I have not done much testing around it. You might try asking the Jive Developers space to see if others have done something similar.