Creating a global alias for a SQL Server Instance

Forgive me if this is an easy question, but I have tried finding an answer but I really don't know what to search (I'm a software dev, with only some limited DBA experience). We have test SQL servers setup with 3 instances each:

TSTSQL01\Enterprise
TSTSQL01\Warehouse
TSTSQL01\Legacy

TSTSQL02\Enterprise
TSTSQL02\Warehouse
TSTSQL02\Legacy

TSTSQL03\Enterprise
...

In production we don't use instances, we have 3 separate servers:

PRDSQL01 --"Enterprise" server
PRDSQL02 --"Warehouse" server
PRDSQL03 --"Legacy" server

Due to limitations of our legacy COBOL application, I am in need of a connection string that has EXACTLY 8 characters to match the length of the production connection strings. What I am wanting to do is create an alias for each test sql server that allows this, using the tstsql01 example above would ideally look like:

TSQL1ENT --maps to TSTSQL01\Enterprise
TSQL1WAR --maps to TSTSQL01\Warehouse
TSQL1LEG --maps to TSTSQL01\Legacy

My current workaround is to use the SQL Configuration Manager to add an alias . This lets me connect to the database on that server, but not on local workstations. Our legacy COBOL app runs 75% of the code from the server, so it works for that. But the remaining 25% of the code runs locally on their workstations. That means I have to add that alias on every single tester's machine (I've scripted it out via powershell, but testers aren't admins so it requires a help desk request for every single person for every single test server). Thanks in advance for the help!