I resolved it myself after trying different configs…and this is the one that worked for me:
”\\xxxx-shares\SiteSoftware\xxxx\Engineering\Ansys STK\Ansys_STK_Pro_v12.7.1\STK_v12.7.1\install.exe” /s /licenseagree /licserverinfo 1055:xxxx-LIC-SRV
If you are testing your silent install script, you may want to re-image your machine before implementing a new script as the licserverinfo is stored.
Hope this helps someone in the future.
You are navigating away from the AIS Discovery experience