Hello,
Not sure I understand the current situation.. The machine needs to be able to reach external resources as well as itself [since the code makes HTTP requests to the API]. You can use a proxy for external resources, so long as it's a valid operational one and if your hostname is not resolvable to the outside world, you can add an entry in /etc/hosts for it on the server and, like I said, on all machines you intend to use Kaltura from to play videos or use the admin I/Fs.
Once your machine is able to reach all needed resources, you can just rerun the configuration scripts with:
# dpkg-reconfigure kaltura-base
# dpkg-reconfigure kaltura-front
# dpkg-reconfigure kaltura-batch