Yes, Deimar spoke truth. When they find the escape routes, they seal them or set guards.

( Holes in a mountain's walls are sadly less subtle than men might wish them. Haiva's smile turns apologetic once more. )

We've tried to set magicians to cover the entrance and exit ways with sorcery, but... the sudden presence of persistent magic draws Rathakku's scouts, inevitably. ( Even so, placidly: ) So, we find new routes. Attevar is long and broad.