He was looking for shiny duscull, but he came down to 8.5m for it after negotiating for a week.
Best chance you have for getting it is to give him a "comp" shiny, he doesn't really know shiny values.
Ign ShinyPokeTrainer
Want to breed these:
Flygon Jolly 25+/31/20+/-/20+/31
Egg move: Quick Attack.
and
Weezing Bold 31/-/31/25+/31/-
Egg moves:Will o wisp, Pain split, Memento
I need both female.
Check PM too.