The good part is once your husband receives his tazkira inshallah, one quick option is that he can go right away to Islamabad VAC and submit the passport on the same day, whether he goes by air or by road. But of course he should leave in the early morning and submit the pp before 4 pm I think it was. My brother-in-law took an older lady with him so before the Paki police bothered him in Peshawar, he gave the pp, money, and other important docs to her because women don't get searched.
Another good thing is if your husband does get the tazkira by the end of this week, he still has around 1and a half weeks til April 3 to submit the pp (March 23 - April 2).
All this is hectic, I know. We had our share of problems and stress as well. But once we took action and everything went through successfully, there was a calming sense of relief. And we really have to put our trust in God that He'll make everything right eventually, especially in the most stressful times.