Kylie, I think we're still missing each other here. What I perhaps should have clarified in the sentence that you quoted above is that "I've successfully shared a .mmpk to AGO as a hosted item [...]". What I want to do, though, is host the .mmpk on our own server not as a hosted item on AGO. My starting point was using the Share Package geoprocessing tool in Pro to get my .mmpk hosted by esri and shared/accessed via AGO. Now I'm trying to figure out how to host the .mmpk internally.
I hope that is clear.
I am pretty familiar with the 'Make Offline Maps' document that you suggested; that is, in fact, largely how I got as far in to this process as I am. When I go back and look at the Share Package tool in Pro, however, I don't see any way to specify where the package is to be hosted. Seems like it defaults to esri. From that same doc I did follow the instructions found here forPortal for ArcGIS documentation. to 'Add files from your computer'. This process got my .mmpk up in AGO alright, but I still don't have any reliable way of determining where it is hosted!
Bottom Line: When I can look at an item in AGO, how can I tell from where those data are being served?
Thanks,
CP