This is basically the one reason why I use Emby as my end point for our household users. I use ChannelsDVR for the TVE channels only at this point (which it's great at), and just pipe those into Emby via M3U. I require guide data to be assigned independently per channel for several other sources, but ChannelsDVR doesn't support this, while Emby does. Emby allows me to setup as many Gracenote EPG sources as I want and bring in as many third party xmltv EPG sources as I want too, that are then ALL available to be mapped, channel by channel, regardless of the channel's source. This allows me to have the most accurate and complete Guide data possible.
If ChannelsDVR supported this, it would be the only thing I'd use, because it is better in just about every other way.