I'm trying to figure out how to install the latest enterprise edition using n98-magerun. Can you install from a zip on the local filesystem using n98-magerun? Is the latest Enterprise Edition available on a git repository?
Yes it's possible. See Wiki for instructions:
You can add new installer sources in your config. n98-magerun uses an embedded composer which can handle i.e. git, zip or taballs as installation source.
You can find the default config here: https://github.com/netz98/n98-magerun/blob/master/config.yaml
All your config will be merged with the dist config.