The Insight table auth has the information about authentications, so it is very similar to what you will see in Access Tracker (or it may even be the same).
The endpoints table in the Insight database is similar to what you see in the Identity - Endpoints section in ClearPass, so it carries profiling data and information like the last known location and IP.
I haven't seen full documentation on the Insight DB internal structure, and be aware that database structures may change over time without prior notice which is why using REST API is preferred, in general, to get to or manipulate data. For Insight reports, I think there is no alternative.
If you contact Aruba TAC, I'm pretty sure they can help you get the required data out. If you insist on investigating yourself, when you enable external database access, you can use a SQL browser to find the structure and content.