Evan is not one of the Five Heroes !?

No, it means that it was Maplestorys original hero, as in the first one, as in it existed before adventurer jobs.

By that definition Aran should be the very first Hero even before his otherwise presumably contemporary company.
MapleStory's first Hero rises again != One of MapleStory's first Heroes rises again (by your definition)

Then there's this piece of text in the introduction

During the age when the Black Mage ruled Maple World,
five heroes protected its citizens from his darkness.

and

the last faithful believer of the prophecy—the revival of the heroes—her clan had received long ago

which include Aran, I'm assuming.

Of course there's no credibility in Nexon's words and everyone who buys it is a donkey with less than half a brain. I'm just positive there's more reasons to perceive things this way rather than otherwise.