"The following steps are optional. You can immediately head to La Theine Plateau without talking to either Chanpau or Morjean and still complete the quest." - http://wiki.ffxiclopedia.org/wiki/A_Squire%27s_Test_II
I went to Ordelle's Caves, right after talking with Balasiel, and followed the wiki's directions to get to the "???" in the water.
The text i recieved from the "???", in the water, is, "I am going to stay here and observe the caves for a while. Watch out for fiends, eh!".
I do not recieve any keyitems at all.