The fact that Indians don't know why the security reasons are confidential matter suggests the mission has been accomplished.
No one in sane mind will oppose khaala baat dam for the betterment of Pakistan except for the obvious reasons that needs not mentioned.
Big dams have potential negative consequences which need to be factored. I do not know the exact merits and de-merits of Kalabagh dam. It looks like everyone outside Pakistan Punjab was opposing it. It does not make for a promising outcome.
In my opinion the red flag on CPEC has to do with the power generation projects. Pakistan needs power for economic growth. I understand that part. But the financial details behind the power generation projects need to be worked out. Otherwise the end users of electricity in Pakistan will pay for those power generation projects. The investors in those power generation projects will make out as bandits