You are way too intelligent to actually believe this - me thinks you are trolling Pakistan here
Falklands is a tiny dependency of UK and it cannot afford to be independent even if Argentina did not claim it. It only has 2,000-3000 people and could not afford the basics of an independent state like embassies around the world for a start.
You also need to take into account that BD Muslims are way different to Muslims of what makes up the current Pakistan. They on the whole are tribalistic and fuedal and we are more into the concept of the Bengali state where are all equal and going towards a common goal of a developed modern state.
Anyway, even if Pakistan had allowed Bengali domination of the country, the chances are that BD would have decided to go independent anyway as it would have found the current Pakistan too burdensome with it's ethnic and tribal dynamics.
The whole idea was stupid from the word go.