there's a reason for that other than just desperation. see, my theory is that the dark mark is made with magical/enchanted ink that takes a few weeks to settle. before those weeks are up, any magic used on it will be excruciatingly painful and make it difficult for the mark to work properly. the mark will also assume that you're trying to remove it, and it'll send an alert to the person who gave you the mark. so muggle methods are really the only safe way to go.

from all that i've heard about boarding schools, it's very very likely he will.

thank you for the comment!