From Power BI desktop we connect to SQL Server on our development database server with a (recent) copy of the production database. After publishing we want to connect to the live database on our production database server; however, this server needs to have the same name (or IP-address) to get the data through the gateway. We solved this issue by adding an entry to the .hosts file on both the laptop with Power BI desktop and on the server running the Enterprise Gateway, both pointing to the IP-address of the proper server. I'll have to admit it is a dirty hack, but hey, it works, so maybe it provides a solution for you too when you seek to use a different server using the same name in both environments. I could not find any information on whether SQL Server instance aliases are recognized by the gateway; you'll never know waht happens exactly under the hood.