The college mills originated in private for profit schools, private schools account for 10-15% of total second degree education, from what I could find about 20% of those could be one of those fraudulent college mills. And consequently, about 10% of the total Indian students go to private schools, so it's a relatively small slice of the overall pie.
It's true though that a lot of Indians, and particularly those from the Punjab region were massively over-represented in these college mills, but the vast majority of Indian students attend public schools, and those were not part of the college mills scandals. It's also important to note that these college mills were created by Canadian institutions, a lot of Indian students were not perpetrators of the fraud, but in fact victims of a corrupt system from Canadian soil. I'm sure it's not fun when you've fork over 20k $ years worth of savings by your family to attend college in a foreign place and you end up with a whole bunch of nothing.
Like I already mentioned earlier, Punjabi are over represented among Indian students, but they are not the majority of the overall Indian body of foreigners. Indian immigrants and Indian students are two different groups, with a 75/25 division. The vast majority of the 75% immigrants already got their degrees outside of Canada, so they aren't really part of the college mill conversation.
Hillbillies don't go to college or show high social economic mobility, Indians do, including the subset of Punjabi's. The second generation also generally do even better than their parents. There's also a granularity to Punjabi's, not all of them are from rural area's, a part of them comes from urban places that typically show higher base of education. And like I told that other poster, you can't just superimpose this profile of the stereotypical rural Indian on the average Indian immigrant, they are not interchangeable.
There's probably some big overlap with the college mills and the 20.000 no shows, but it's in relative terms it's about 5% of the overall group of Indian students here. Also doesn't seem to be worse than the no show rate of overall immigrants, both in Canada or other first world countries. I checked and lot of them are around 5-10 % to 15% in the more extreme cases. Students from some African countries (Congo, Ghana, Nigeria) have higher than 30% no show rates in Canada, but do they come here in vast lower absolute numbers, so I guess it's perceived as less of a problem.