They don't. No retrans agreement = no guide data (even for ota reception).
There are channel that are not even on DISH that have OTA guide data, so I don't think they need an agreement.
isn't the ideal solution for dish to have as many OTA viewers as possible, keeps costs down in many ways too, that way they disputes don't really matter as much... and if during a dispute they expect viewers to watch it OTA wouldn't they want to show the customer the guide so they can have the best experience possible?
I also think the guide data for certain National subchannels is the same across multipltle channels, so that might result in THIS TV or Bounce staying up on XX-2 while XX-1 is disputed.