Alright, I really need some help on this. Right now I'm trying to clear the Jungle Ruins of Si Khem(A Lv13 Dungeon of Hard) that unlocks a second Academy which I desperately need. I already have two Temples and two Game Halls, so the Black Magic is the only thing I'm behind on(which ironically enough, was the one I was trying the hardest to get from day 1). It's one of the dungeons that changes shape each day, but despite my best efforts I can never explore enough to lock it into place like I can with the other change shape ones.

So far I have all 16 adventures unlocked with max pay rank(I have 5 Warriors, 4 White Mages, 4 Thieves, 3 Black Mages) so money shouldn't be a problem for them. My highest is level 25(Warrior) and my lowest is 11(Also a Warrior). Everyone else is between those levels, around an average of 16.

Each day I send around 6-8 adventures to the Jungle Ruins of Si Khem, 2-3 of which are thieves, yet I never explore enough to cross the threshold. I have the Mapper ability researched to lv20 but the thieves seem reluctant to buy it(they refuse to even visit the game hall, instead going to Weapon Shop, Item Shop[Every day, in that order] and either the Training Hall or Armor Shop alternating for the third shop before setting out).

Anyone know how I can get the exploration rate I need to stop this dungeon from changing so I can unlock the second Academy?