May I suggest that you change "Considered by some to be the most difficult 4 player dungeon currently in the game" to Amdapor Keep instead?
Wanderer's Palace is really easy even if you're a fresh 50 unlike Amdapor that will probably get people stuck at Demon Wall if they're fresh 50s.

Also here's a list of tombstone rewards:

Philosophy:
  • Stone Vigil: 20
  • Dzamael Darkhold: 30
  • Aurum Vale: 40
  • Amdapor Keep: 80
  • The Wanderer's Palace: 50
  • Castrum Meridianum: 100
  • The Praetorium: 100
  • Ifrit: 10
  • Garuda: 15
  • Titan: 20

Mythology:
  • Amdapor Keep: 40
  • Ifrit: 4
  • Garuda: 7
  • Titan: 10
  • Coil of Bahamut (turn 1, Caduceus): 40