Not using the answers file, but since Foreman 3.3 you can use custom-hiera.yaml to add additional Apache modules. This is somewhat unsupported in the sense that if it breaks, you get to keep the pieces.
I’d recommend taking a look at the module file and config template:
It would be interesting to know what you’re trying to achieve here. Mostly because Foreman is often used in a very controlled environment where GeoIP isn’t really relevant (given you can’t do that for RFC1918 IPs).