When Database.Object() is called and the table joins are explicitly or implicitly created (via ObjectReferenceEarlyBinding) then an Ambiguous column name error occurs. For example:
SELECT * FROM ([ReferencingTable] INNER JOIN [PrimaryTable] ON [ReferencingTable].[ItemID] = [PrimaryTable].[ItemID]) WHERE [ItemID] = 11 AND ([SubSetID] = 7) ---> System.Data.OleDb.OleDbException: Ambiguous column name 'ItemID'.