1 If your close relative is a permanent resident of Canada: photocopy of his or her Record of Landing (IMM 1000), Confirmation of Permanent Residence or Permanent Resident Card.
2 If your close relative is a Canadian citizen: proof of Canadian citizenship, such as a photocopy of pages of a Canadian passport or Canadian citizenship card.
Given the above emboldened words. Let her send any of these. I have the same issue with my Aunty who believes there are security concern over sending the bio page of her passport. But I ask her to send the certificate of citizenship only. Which she agreed to do.
However, I need to say this. Don't just put it aside. There is always a political solution to most problem in life. Educate, persuade, convince her to give you what you asked for. Its not a time to call someones bluff, but a time to supply all the documents you need to. Immigration matter are usually long endurance trek if you permit me to use that word.
I wish you the best. Peace.