The Pace DS830NS HD uses XMP1 protocol which stands for "eXtensible Multimedia Protocol". There is also an XMP2, XMP4 and XMP 32
This is a very common protocol because it is also used for things like wireless keyboards etc.
There is no way of knowing if it is used on the 831 without actually testing it by capturing at least one command from the original remote.
Either way you have apparently already tried all the Pace PUC entries, so we can assume that even if one did use the XMP1 protocol it is almost certainly going to have a different device code, so it still would not work.