Some how drifted onto this thread from the one on Bransby's route. Not that I'm much of trad climber but it intrigued me, so I thought I'd see what info there was.
If you go to the 'other channel' and check the log book there is quite a bit of info regarding the peg. Supposedly a grey camalot will fit to back it up. Rob Greenwood also wrote this "Abbed down to check the peg beforehand. Considering its age it looked ok, didn't realise it was concreted in either! Could be backed up well with a large Alien."
Sounds like the peg, which is cemented, can be backed up. Maybe just go for it?