It reads to me like 3 would apply here - they don't have jurisdiction over unrelated data stored elsewhere (else data-havens would not be a thing) by a company

It reads to me like 3 would apply here - they don't have jurisdiction over unrelated data stored elsewhere (else data-havens would not be a thing) by a company headquartered outside their country (AFAIK - IANAL). I read it as: FB wanted to store [whatever data they wanted] in Canada, and didn't want Canada to impose any rules on [outside-Canada data]. Basically they wanted a data-haven. Not all that surprising of an ask, but I don't think Canada does that in general.