Hi Lucas
The assignaments of OCMJEA has several jokes and one is have some entities in BDM without proper description. In this case you have two options:
1. Delete entities explaining that you did not understand or did not find reasons for them.
2. Assume anything you create features for each of them.
In my assignament when I was approved, I had 3 entities in my BDM that lacked description. Within the context, I had several assumptions that could give life to these entities. I chose to use the more consistent within the context of business.
And do not forget, you as an architect can do anything in your project. Do not forget to coherently justify every decision.
Regards