Tested this on my 2160 and got the same result. I can't remember trying to dub a finalized disc to the hdd before, but you can dub an unfinalized disc to the hdd. So, if the disc you want was recorded on the Magnavox, you can undo the finalization, and the dubbing option will now show.
Dazed and confused over high tech.
Sigh...Concrap. The Internet Overlord Cometh
They're not com-tastic!
The help file on Dubbing Finalized and Unfinalized discs to HDD is here.
A list of other help files is here.
PHILIPS HD DVRs | MAG/PHILIPS SD DVDRs* | DVDR/DVR COMPARISONS | POST-DVDR OPTIONS
*Due to the AVS SW change in June 2014, most but not all links in this thread will work if you're not logged in. If you are logged in, links should work if your User CP > Edit Options > Number of Posts to Show per Page is set to 30, the default.