I also don't think it's specifically made to be a magekiller dungeon, but might be valid to note that since magic users are exponentially dangerous at higher levels, countermeasures designed to stop them will probably be a lot more flashy, obvious, and purpose-built. So we may not pay attention to the giant physical monsters and instead focus on the time she uses an AMF, because that's out of the ordinary (but a totally justifiable precaution against high-level characters).

Solution to keep out a high-level fighter or rogue? Just put more dungeon in your dungeon and nobody bats an eye.

Solution to keep out a high-level wizard? Some tricky bull****.