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My lot are orignally from Rohtak, (they would love to speak like Lukhnawis!!!), and I can tell from personal experience, that the Shaukat administration tried there hardest to keep the Ambala Division refugees (non-Punjabis like Meos etc from East Punjab) out of the province. Sarah Ansari has written quite a bit on this.
Rohtak and ambala division is part of present haryana state in india.Majority of muslim refugees from haryana,indian punjab,himachal,jammu-kashmir and rajasthan were mostly settled in punjab province of pakistan.There might have been some exceptions but they were rare.
There is also another story which goes that gandhiji had persuaded the meo muslims of mewat district to stay behind india.
Another thing is that most mohajirs who came to punjab mostly got assimilated with native people just like the kashmiris who came to punjab a few generations ago got integrated with punjabis.