Ya I'd bet Paragon got a number of server first 90's (maybe all of them) and likely did chain heroics like mad men till MV opened, and loads of dailies, then got some VP gear and any crafted get they could before MV opened.
Based on my Ilvl and what is available in heroics I'd bet they had ilvl 470 before MV opened.
Also I'd bet they did black prince rep in the first week.
so with the kind of dedication to the game as they have its not that far fetched that they would be 6/6H pretty fast.
Other than the swap at the pulll at 50 energy, you may need to double taunt if the lone dog starts charging, the fight seems straight forward.
Always pair the petrifying dog with the one that just blew up, if they are on the same tank awesome if not taunt accordingly. -- Judge a man by the trials of his shield, not the empty reaping of his sword.