Yes, I am able to enumerate mDNS names with:
avahi-browse -a
Alternative idea, which probably could be a bit controversial, is to use an mDNS name hardcoded in the kickstart config, like fedora-installer.local.
This option should be configurable, including possibility of disabling it completely.
For small-scale use, it would be helpful. For fleets of computers, an automation would anyway be required.
In any case, the installer web page shall display the IP address and possibly other identification (MAC address, BIOS machine id/serial number) of the machine being installed. This will be useful even without mDNS.