On Amazon SQL Server RDS, how can we identify all apps that are connecting using the direct server name and not the alias?

Question

We are soon to migrate our back-end from an Amazon SQL Server RDS to another identically set up RDS server. We intend that our systems will not be interrupted because they connect using an AWS alias that we will swap to point to the new RDS server. While we believe all our systems use the alias and not direct server addressing, it is possible that we have missed the change in some application code. Can anyone advise a method we can use to identify applications that are connecting without the alias? Is there anything to indicate the connection method from with SQL Server Profiler? Is it possible to log what applications use the alias from AWS?