Moroccan & Canadian work visa?

My father has been living in Morocco with his wife for a few years. They have been trying to get her a Canadian visa to come here. She applied for a vistor's visa 3 times and was denied. Then my grandmother put an add for skilled foriegn worker on the job bank, and said she would hire her, or give her complete ownership of the business. The government of Canada approved her for a work visa, but the Canadian Embassy in Morocco didn't because they said there was no proof she would go back. She does have parents in Morocco, and she owned a cafe there but it's in the middle of shutting down right now. They were married in Ireland, so technically their marriage isn't legal or what not, so they didn't bother telling the Canadian government about it, as it would hurt her chances. Should she apply for a student visa? I think the work visa might be the best shot, but how do we prove she will go back to Morocco? Is there any loop holes or anything? We've been trying for a few years now and can't seem to get any luck. Any help is appreciated! Thank you!