People who are on USA wanted list are known to everyone. They are typically not the “missing persons”.
Missing persons in Pakistan are typically Islamists who have ended up in FATA and Afganistan on their own will.
Just like the 5 Pakistani-origin men from USA, who got caught in Pak while planning to disappear in Afghanistan.
Had they not been arrested, these men and their Jihadi supporters would be maligning Pak army by their fake disappearance.