This should also be possible with the guardiness stuff, as long as you can arrange fresh consensuses to arrive on the second host.
tor supports consensus downloads without being a router, but it's a bit of a hack:
A tor instance configured with a DirPort and no ORPort will act as a directory cache only. Directory caches regularly download the latest consensuses.
It's worth binding the DirPort to localhost only, and marking it NoAdvertise. This hides the cache from the consensus, and disables remote requests.
However, the cache will also download router descriptors unnecessarily. (Microdescriptors and extra info can be turned off, but I'm not sure if router descriptors can.)
If all he's after is to fetch the latest consensus or votes then that's pretty simple (no hack or running a local tor instance necessary)...
https://stem.torproject.org/tutorials/mirror_mirror_on_the_wall.html#where-c...