Jason, sometimes you have to scroll way down on the flight list to find the Delta operated flights. If you look at NOV 23 from ATL-PVR you have to scroll way down to find the ATL-LAX-PVR option.

Also, it looks like Delta only flies down there on Fridays from LAX and Saturdays from ATL. I would have ZED backups with such low flight numbers. US airways to/from PHX and United to/from IAH. Or one of the mexican airlines to Mexico city and then try Delta from there.

As mrs767 said, it looks like a tricky place to non rev to.