Yes. One user can be assigned to two or more dinHVDs. That is not possible in the same computer group, but you can create another computer group in the Connection Broker and assign the same user to another HVD is the second computer group. Similarly, you can create more computer groups and assign the same user to multiple HVDs (one dinHVD per computer group).
When you assign multiple dinHVDs to a user, that user will see an additional icon for each assigned dinHVD in their Web Access/App portal.