Pakistan must need to take this matter up with important capitals of world. Indian involvement in Pakistan still exist. Completely agree with the OP that Strict border management is required on Pak-Afghan Border.
I am worried that how CPEC will be safe guarded if thousands of people from Afghanistan cross Pakistani border daily unchecked. This is just horrific and terrible situation.
Pakistan is suffering due to lack of lobbying/diplomacy. India covers up all its terrorism by its economic, media and diplomatic clout. So no one pin points India. It also uses Terrorism propaganda against Pakistan to hide what she herself is doing in Pakistan. Just look what India did with Nepal (blockade of supplies), heck not a single world power noticed it. We need to look what makes India so bold and confident that they make such aggressive and bold moves against their all neighbors except China. We never see any Indian Gov't going aggressive against China or threating them, Why? Do we have an answer?
We Pakistanis lack far behind Indians in creating perception/mind game. In today's politics, you don't call your enemies as your foes, you call them terrorists. So, that you can prepare whole world whats coming next if bad guys(your enemy) do something. Pakistan must need to propagate its point of view to every channel available, not leaving a single opportunity for Indian fantasy. We need to read/prepare/advance/adopt Psychological warfare because it is being imposed on us. Chinese can help us out though.
Les read The Art of War Book by J. H. Huang and Sun Tzu........