It's to bad we did not see him. They could of had an episode where the Galactica found the last Daniel living somewhere, etc..
The reason they couldn’t was that Moore was continuity obsessed and it would make the Angel’s statement to Baltar there are twelve models false.
If you noticed, in Razor they rescued two humans at the end. The reason? They killed two humans and the survivor number did not change between the two episodes Razor happened between.
Edit: Or was it Caprica who told him that before she blew up?