Yes: neither have enough NI credits for the full state pension, so if they don't have other pension provision, they qualify for Pension Credit.
It's not because they're immigrants, it's that being an immigrant is one of numerous reasons you might not have a full NI contribution record. Being a stay-at-home parent for a long time, being a carer, working your whole career in public service (so you'd have been contracted out) are others.
I think what
@Simbindi was saying is that people who are entitled to the full state pension could be in a worse position than people who aren't. Provided they have no other income, both groups get the same amount of money each week—but because those who don't have the full state pension get part of the amount as Pension Credit, they
also get the passported benefits.
They might not have to pay council tax at all, for instance, whereas the person on a full state pension might get a lower discount. Ditto winter fuel allowance, help with optician's and dentist's fees, cheap broadband deals, etc. It could potentially add up to a lot of money per year, for people who're on exactly the same basic income.
[Edited slightly for clarity]