Its not the matter of whether the government will allow or not allow. its what they are offering. and they have offered key positions to PTI in the committe to do the investigations under their supervision. you have to give a chance to these things.
also, to get to what you are asking, resignation of NS will not help. government has to go, because you cant guarantee investigations under the government.
furthermore, same rigging happened in sindh/karachi. that means MQM/PPP will loose everything. but they are very aligning themselves with IK demand. the question is, why? why would they allow investigation into rigging? Geo made videos of rigging and ballot stuffing in karachi.
also, IK came to power in KP based on the same elections. why did he accept that mandate and made his government?
finally, the question is, why the quest for one person removal? this is what is extremely shadowy. now, army is pushing government to resolve this quickly instead of telling *both* of them to be flexible.
this is not about election rigging. this crisis is made elsewhere and for a different purpose.