Really, no FAQ entry is needed on this one. The answer is "Yes". The player's probably been confused by semi-reading discussions of attack-of-opportunities versus reach weapons. For example:
Q #1: I try to disarm someone 10 ft. away. Do they get the resulting attack of opportunity? -- A: No. AOOs require the target to be in a threatened zone.
Q #2: I try to disarm someone 10 ft. away. Do they get the resulting counter-disarm if I fail? -- A: Yes. The counter-disarm is not an AOO, and nothing in the language on PHB p. 137 requires the target to be in a threatened zone.
(This assumes a normal circumstance with a Medium-size opponent, no reach weapon of their own, etc., etc. The only wiggle room for a rules lawyer would be to argue the counter-disarm also provokes an AOO, but certainly not that they need to threaten to attempt it.)
