@brodtgaard I don't quite follow the questions, but I'll try to answer. The preface here, is that I thought there were restrictions on sharing from PBI groups, but I just tested out a bunch of scenerio's and it appears that there are none now...
I have full Office365, so I have all the capabilities of a PBI Group.
I see no restrictions at all, and I was able to:
Create an Org Content Pack in a PBI Group and share to another PBI user
Connect to a (3rd Party) Content Pack (Lithium) and share that with another PBI Group
I apologize for not formulating this better in the first place.
When I want to subscribe to a content pack from within a shared group (not from my own workspace) then it seems like the content pack needs to be set available for the whole organization and not just for some relevant users. Is that so?