I found the
user manual online and saw the hex codes that you are referring to on page 44.
That page states that "The HDT100 uses the RC5 IR protocol with the following codes" and it then goes onto list the codes for each function, but what it fails to mention is what RC5 device code (aka "system code") the HDT100 uses. If you could get that information from Motorola, I could create an upgrade to make a universal remote work this unit.
As for the Dish PVR, that remote sends both IR and RF, so you can easily make a universal remote control it.