Why are you trying to compare Chaosbolt to Pyroblast? Pyroblast is nearly like Elemental Blast, and yet Ele blast is doing MORE than Pyroblast even if mage has buffs etc up, EleB will do more.
The mage can easily have PvE trinkets, the PvE gear is useless.
And your conclusion is what? A srs bug and yet you're telling us that it's impossible to do 143k Pyroblast in deep freeze? Oh what a conspiracy! The player did 143k Pyroblast, your "conclusion" can be very wrong, genius.