In v10.2 of the Microsoft JDBC driver for Microsoft SQL Server, TLS encryption is enabled by default.
This means that the JDBC driver will attempt to use TLS when connecting to the SQL Server and if TLS is enabled on the server with a self-signed certificate then the IG installation will fail because the certificate can't be verified by the installer.
The workaround is to use an older version of the JDBC driver, e.g. v9.4 so the install completes.
Afterwards you can switch to a newer driver (after trusting the server certificate) or you may also change the JDBC URL if you want to disable TLS encryption with a newer driver.