It really would. Not that Five is worried about his brother dying before they find him, but he doesn't doubt that he will immediately escalate the situation. He should enjoy this relative peace while they have it. -- You know, if you overlook the harpies, the highly suspicious ghost army, and that horrible oppressive agony weighing on his chest that he's currently ignoring. Total peace.

"At least he's consistent." Just imagine what the stupidest reaction would be. They'll track him down in no time. "Luther and Klaus could take longer, but Luther doesn't exactly blend in. And Klaus should feel right at home with all the spirits and undead hanging around."

He's actually more concerned about the latter being able to deal with all this, even if his powers would be the most beneficial. It's for the best that Klaus missed out on the cult of undead worshippers they just left behind. (Well... almost left behind. That old man he spotted earlier is impossible to get rid of.)