If you look at Manitoba PNP here:
http://www2.immigratemanitoba.com/browse/howtoimmigrate/pnp-eligibility-criteria.html there is a thing called strategic initiative where prospective immigrants can ask for an interview with the PNP during their exploratory visit. If your family were to do that and they meet the requirements for the strategic initiative and have good employment opportunities, they might be invited to an interview and might be allowed to apply under PNP without a job offer.
However, it is likely that they will look at your fathers age in a negative light there also because he does not have many years left to work. Retirement age in Canada is 65 and so he has only 7 years left. They might not feel that it is worth it to let him immigrate for only 7 years.
He could however try to get a job offer and apply through another PNP or through FSW. You could also try to sponsor your parents under the federal program when it opens again after 2 years.