The terrible truth (bugged)
I assumed that the question mark was applicable to a surface location, since I had earlier found in the same caves a yellow exclamation mark for the Grummle's yak replacement quest, which I knew to be on the surface.
After leaving the caves and finding nothing on the surface at the location of the question mark, I went looking and found that the mini-map was directing me to return to the Shado-Pan base; however, Tai Ho can no longer be found at that location.
I then found in a comment on Wowhead (http://www.wowhead.com/quest=30926/the-terrible-truth#comments) that logging out and relogging would solve the problem. Apparently I could have logged out while still in the cave, but I hadn't known about this and so had to travel back through the cave after relogging.
I started this quest several days ago, but could never find the turn in. I had checked the cave originally, but nothing was there. I looked at the map & it pointed out where the yak replacement quest starts & finishes; but nothing was there. Another time the turn in location was directing me to the Shado-Pan Garrison but nothing was found there.
Today after I shut down the computer for the night, I restarted it to play a little more. I went back to the garrison, & couldn't find anything. Then I flew by the Temple where the quest started, & didn't see anything. I flew to the yak guy' location (he wasn't there), & nothing. I finally flew to the cave, went down the bottom level; & it was there where I found the turn in.
Man there are a lot of bugs with the Pandara still around, even after how long it's been released.
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