Aren't the photos saved in the iTunes backup? It may not have all of them, but when you back up your phone I think if you restore from a previous backup then you could possibly retrive them. I may be wrong, but I read somewhere a long time ago that it was an option. Have you ever backed up; not sync'd but backed up?
Once you do that, grab those photos (if it works) and then recover deleted photos from iPhone via the latest backup.