As a healer, if I roulette and get an Amdapor I will state that I suck at marking doors, and ask if anyone else is decent at it. If someone is, great! But if I get no response (sadly, the most common), or they all say that they suck at it too ( the second most common), or "That's okay, we'll wing it!', I will say "Sorry, I don't think we'll be able to complete this dungeon. Better luck next time." and leave to farm atmas.

In this situation I don't believe I'm in the wrong, as it's quite obvious that the assembled party lacks an integral willing component to complete the dungeon.