Because basically it suits the Paki's. Its a load of crap really but since he was detected by "in house testing" his future is at the mercy of the PCB. They decided it was "accidental" so they let him off.
Had he been detected by WADA he would have been banned for two years no questions asked. It was funny when him and Ahktar were left out of the world cup team due to "injury" after thay had private drug tests.
I would say they still had drugs in their system and couldnt go to the WC becuase they be tested by WADA and then banned. They had to leave them out so they couldnt be tested until the drugs were out of their system.
Its all BS.