CRA advises in their “questions and answers section”

“Can a registered charity lend us its registration number while we are waiting for our application to be reviewed?

Under no circumstance should a registered charity lend its registration number.  A registered charity is responsible for all official tax receipts issued under its name and number and must account for the corresponding donations on its annual information return.  Lending the registration number to another organization could lead to the revocation of the charity’s registered status.  In addition, a registered charity that issues incorrect or incomplete donation receipts or donation receipts that contain deliberately false information is liable to a penalty.”