If you have to submit the photos in person, then your PR card will wait until you can get back to Canada to do it. This will in no way affect your PR status. The only thing is if you wait more than 6 months after your landing, you lose the chance to get your first free PR card and once you are in Canada again, you would have to apply for one and pay $100. As for how to get back to Canada without a PRC, you can use your landing documents if you are visa exempt. If you are not visa exempt, you have to apply for a PR travel document at the Canadian embassy.