You are better off keeping that device list separate. In excel if you must, or some other database. Add a column to that device list data where you, for example, add into that column, for that device, that it has been assigned to <unique user Id, like your Active Directory\Username>
Then, you engage your database people, the ones who are good as creating reports using data from multiple data sources, and tell them that 1 data source is the CM database, and the other data source is <that device list data you are maintaining>, and that the common denominator is that username.