2x Drop cards @ Mini Dungeons?

Hey, just finished patching and I just got 6 tickets to the Mini Dungeon event in the cash shop. After using all 6 and only getting 110 crystals (I messed the first 3 up) i'm thinking i'll need 2x drop in order to get the moon chair thing

but!

a lot of people on my bl / people i've bumped into in game have said 2x drop doesnt work inside the dungeons (specifically ant tunnel 2 dungeon, that's where i plan to hunt) so can anyone either confirm they DO work or if 2x cards DON'T work for the crystals in mini dungeons?

side note : sometimes on 1x drop i would get 2 crystals from a single monster, so that isn't certain proof of 2x drop working, however i only got this from 2 monsters out of 6 tickets so its rare.

This thread might help a bit

http://www.southperry.net/forums/showthread.php?t=4527

im inclined to think it works, i dont see anything special about the enemies that would have 2x drop not work... ive also gotten 2 crystals from one kill pretty often which makes me think 2x drop works for sure...

a like level mage i know got an avg of 20-30 a go without 2x drop, i got 50-55 avg a run with 2x drop, so far in every comparison ive seen from bl/guild 2x drop does work