This is probably the hardest part of the epic, since Sev is such a bitch to camp, plus there there's a chance the scale might not even drop at all! Yes, you kill a huge green dragon, and there's not a single scale that you can use from it! Lame.
Alternately, the scale also drops from Hoskar in Veeshan's Peak, but seriously, who warrior with access to VP would want their epic in the first place?! Thanks VI for making no sense whatsofuckingever.
The #1 question I see asked about this part is "Can I use Emerald Dragon Scales instead?"
No no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no no you most certainly cannot!
Emerald Dragon Scales are a drop from Wuoshi, a dragon in the Velious zone Wakening Lands. The Emerald Dragon Scales are part of a completely different quest for a 20wis BP. Besides, the epic quests are Kunark-era, so obviously a Velious-era mob would not drop an epic piece.
But if you're tard enough to go ahead and try it, you deserve all the ridicule that you will get from doing so.