Well, he may not. Would he be considered single when he cross into Canada with his work permit if he did online nikkah? Would he be considered almost married?
If not legally married by IRCC regs, and any online/by proxy/not-present marriage won't be recognized by IRCC, then yes, still single.
Next: is it required anyway that someone entering on a work permit disclose marriage (that happened between getting the visa and arrival)? I don't know - but not critical or relevant anyway, because his 'spouse' is already a PR anyway.
So every way they cut it - as far as I'm aware - no harm, no foul.
I guess we do not know if online nikkah will be questioned. But they should not try to hide it from IRCC.
I see your point. But see my points above - not a marriage in IRCC eyes anyway.
So before reading the below: I have my opinion but this part of it not strongly held; maybe it would be better to disclose to IRCC this non-marriage ceremony.
And my related point is, why raise the issue of whether they did a 'complete' traditional marriage anyway? They know they didn't. They are not even going to try to register it. It's not an arranged marriage (where more critical). They will have a court marriage and be residing together. If they want a 'blessing' or some rite to not feel guilty about living together, as long as that rite is not actual legal marriage, what's the issue?
And repeat point: if IRCC did find out about it, there's no basis to believe it constitutes misrepresentation. (IMO).
Again, I end up with 'no harm no foul.' But I'm not going to claim to expertise in Pakistani marriage customs and the related issues. Nor how IRCC will see this as a strength or an oddity requiring further inquiry.