Someone youthfully exuberant would not have been able to hold back on telling the world about the development and feature plans he was so excited about and instead wait until after the instamine was entirely completed. In fact he did exactly that which shows it was likely purposeful and calculated, not accidents and mistakes.

Evan had been around crypto for at least two years or so before launching XCoin/Darkcoin/Dash. He'd see it all, including premines, hidden premines, instamines, etc. He was no beginner and he knew exactly how to play the game.