If the map causes xp loss and mobs can kill players in seconds...

... then the mobs should drop loot like normal.

A map that's 6 or so levels below you is still plenty deadly, and you will lose 10% of xp on death. Yet an elite won't drop any loot.

Pick one:
a) There are no rewards for players, and therefore, no xp loss punishment to the player.
b) There are rewards for players, and the usual overly harsh penalties apply.