1. Yes. Absolutely.
2. None. (Well they'll do criminal records check and the like but nothing more substantively).
3. Relax and stop stressing. You're Canadian PRs. You've been there for 3 1/2 years, including more than a year as PRs. You settled and worked in the province that selected you. It's clear you honoured your commitments. Nothing whatsoever to worry about.
There IS potentially an issue for those who clearly never settled and never tried even to reside in the provinces they were selected by. It COULD be treated as misrepresentation (i.e. if you 'gamed the system' and never intended to settle there). But to be put it simply, this is relatively uncommon, we don't know how many cases come up, etc. Anyone who actually did settle in the province of selection for more than a year clearly has nothing to worry about.