CableCARD shows Auth:MP and apparently no one knows how to fix it...

I had a new CableCARD installed today for a Tivo HD XL. The three technicians (one was just QC) who eventually showed up had never installed a CableCARD and left without any channels working. I called 1-800-COMCAST and managed to get channels 2-21 activated, but that's it. After SIX HOURS on the phone, no one there seems to know what Auth:MP means or how to fix it. They're sending a fourth technician tomorrow, but can't promise me that they'll know how to set up CableCARDS, either. Tivo says a service call isn't necessary and they they need to send an Init Hit or just setup the card anew as it apparently wasn't set up properly to begin with. I'm frustrated to have to take more time off work so that another clueless technician can come in and swap cards for no reason.

I went to Comcast chat and sat waiting for 30 minutes and after I explained three times that this is a new install and they didn't give me an account number (only a job number), they told me to call 1-800-COMCAST. Arg...

Does anyone know some secret way of getting Comcast to get their darn CableCARDS activated?