what do you think would’ve happened to rana if her parents had succeeded in sending her away??

It really does depend on what their intentions were. If they want to keep her locked up, there’s no escaping that. In Pakistan or anywhere else. If they took her to an urban area, that’d be like a city anywhere else, she’d have been able to flag down a taxi or rickshaw or simply ask to borrow someone’s phone while out shopping and eventually make contact with a consulate (and/or Kate).

It might be different if they took her out to a rural area, it’s difficult to get there or get away from there on any public transport and it wouldn’t be so easy to find a phone or internet with which to contact somebody. 

I doubt they’d have tried to physically hold her prisoner, though, I think they would have tried to work on her mentally, guilt and lecture her into changing. I don’t think they’d have outed her, that would have brought shame on them too, aside from the physical danger it could have put her in.