Stuart Law has rejected the chance to become Pakistan coach.
The former Australia batsman had emerged as the frontrunner to take over from Waqar Younis, but schedule conflicts have ruled him out.
Law will work as a batting consultant on Australia's tour of Sri Lanka later this year, ruling him out of taking the top job.
"Yes, there are hurdles in the way of signing on Stuart Law as head coach, although he is our first choice for this position," PCB chairman Shaharyar Khan said.
"He had applied for a coaching position with us but he has now conveyed he is more interested in a consultant's position and that he wouldn't be able to join the team immediately."
Khan revealed that former Hong Kong, Kenya and Scotland coach Andy Moles or 52-Test Australia international Dean Jones are now in the frame.
"We are now also talking to Moles and Jones although the BOG [Board of Governors] had some reservations over some candidates," the PCB chief said.