Storyline related. You can miss the speech challenge (and the achievement) if you don't talk to the upstairs bartender, but instead eavesdrop on from the duct that goes past Tong's office.
As with all of the speech related challenges in this game, there is no one solution, and the dialogue varies. So, what worked for you may not always work.
If you fail this speech challenge you won't get invited to Tong's office, and therefore have to force the story along by overhearing a conversation via the vents that pass alongside the office. Besides getting this achievement, there is also one of the XP books (for Doctorate achievement) in Tong's office, which you won't have access to unless you pass this challenge.
I answered "pinpoint" all three times and got the achievement/XP. However, the biofeedback graph showed the last one as being incorrect.