Well yes and no for Pakistan. There are a lot of Farsi speakers there as refugees etc. but on the other hand this guy may suffer from a lack of geographical awareness.
Farsi is most widely spoken in Iran, Afghanistan and an older and some would say purer form is spoken in Tajikistan.
Now I would say that if they were fluent in Russian and Farsi i would be more likely to place them as Tajik.
This all sound like wishful thinking with a soupcon of divide and conquer to me.