I am getting a weird issue where there is VS2019 installed on the build server but DutchWorkz
MSI Addon only "sees" VS2013, VS2015 and VS2017,

None of which is able to build MSI project due to various reasons like expired licenses and devenv.com not being there...
Is there a way maybe instead of using magic VS2013 VS instance name to pass disk location of where the devenv.com for VS2019 is or some other workaround, or a way how to make VS2019 appear in the list.
Or debug this further on why is it not there.

AFAIK, neither DutchWorkz MSI Addon (old version
1.1.7) nor Build VS Installer (New version1.2.4) support VS2019.That is the reason why you not able to see the VS2019 in the drop-down list.
Besides, both extensions are now unpublished from Marketplace.
To build the MSI Setup Projects, you could use the command line task to invoke the
devenv.com:Steps:
Command linetask"C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\IDE\devenv.com" MyProjectDir\MySolution.sln /Rebuild ReleaseNote: please note to use
devenv.com(notdevenv.exe).