If it doesn't work, she will have to return home and you can expect it will be extremely difficult for her to be able to visit Canada in the future. You will then need to wait until you can sponsor her for PR through the regular parent/grandparent program before you will be able to bring her to Canada.
Have you actually waited and tried to apply like every other Canadian or PR wanting their parents to arrive? The rare H&C approvals for parents encouragea others to apply.