There's no issue as he is a PR now, under the charter of rights he can do pretty much what he/she wants now. If during the application they find out he lied and was living in Ontario and wanted to reside there since the beginning yeah, he/she would be at fault and rightly so. Even if they find out afterwards that from the beginning he/she wanted to live in other place than Quebec and prove it, they could retroactively take their PR, but if they moved afterwards or in a reasonable time before getting his PR, no issue there, life happens.