I've got a Rushmore which is the rear entertainment Landmark. I was able to run a pair of coax lines. In the off-door-side of the entertainment center, if you remove the outlet cover, you can push cable through and out to the corner of the underbelly without taking the underbelly down. Then follow the frame. Drop just the corner of the underbelly near the UDC to. route the cables into the basement and to the back of the UDC. I disconnected the coax from the roof and took over those connectors.
Pushing and pulling the coax took 2 of us working together for a couple of hours.
If using Directv, an alternative is to get a SWM setup. A single wire to the receiver fully supports the DVR. Dish probably has something similar, but I'm not familiar with theirs.