Nearly six million Muslims were expelled from East Punjab by Hindus and Sikhs. As per (higher) estimates, 1.2 million Muslims left India but didn't reach Pakistan, most of them were from Eastern Punjab (an estimated 0.5-0.8 million). Only 2.5 % of those who made it alive to Pakistan, settled outside Pakistani Punjab. As per 1951 census, i.e. four years later, the total number of "Mohajirs" in Pakistani Punjab was 5.28 million. Do the maths and you will get your answers.
As for the immigrants from the five/six south-eastern districts of Punjab (that today constitute Haryana) not all of them spoke Haryanvi. The areas bordering (now) Punjab had a high percentage of Punjabi speaking Muslims. I personally know a lot of people whose ancestors migrated from Haryana districts, they are as Punjabi as it gets. People like Rana Iqbal Khan of Phool Nagar and Hafiz Saeed of Sargodha have Haryanvi origins, but no one ever considers them "Mohajir" or "Haryanvi" ... Rangari, arguably a dialect of Haryanvi, however, is still spoken by a significant number of Rajput settlers, but they too have fully assimilated into Punjabi culture. Moreover, a large number of Meo Muslims from Mewat region of Haryana chose to stay back in India (on assurance of Gandhi) and today are in majority (up to 80%) in a few districts of Haryana.