Well, they replied very quickly:
We do not know of any issues with our guide data or servers, and the channel lineup you have select is still valid for both accounts’ Moxi HD DVRs. One Moxi is online and one has been offline for a few weeks which would be why it is not downloading guide data. You could try rebooting the router and then the Moxi HD DVRs to see if that helps resolve the issue.
Unfortunately, we will not be escalating or looking into this report further for the Moxi that is online since it seems fine on our end, and that system is already flagged as having been voided when the hardware was tampered with so we cannot ensure the software and/or hardware are operating properly.
Moxi Customer Care