You need the Canada visa and open work permit to come back
I found this, looks like she can leave but only to the United States
https://www.canada.ca/en/immigration-refugees-citizenship/corporate/publications-manuals/operational-bulletins-manuals/temporary-residents/visitors/visa-validity-expiry-dates.html
As per
R190(3)(f), foreign nationals who are normally required to have TRVs to enter Canada are exempt from that requirement when they seek to re-enter, if, since leaving Canada after being authorized to enter as a temporary resident, they have
only visited
St. Pierre and Miquelon or
the U.S. (including the Territories and Possessions of the U.S., but not including cruises that enter international waters) and:
- are returning within the initial period authorized by an officer; or
- are in possession of a valid VR, WP, SP or a TRP (authorizing re-entry) and are returning within the initial period authorized by an officer.
An example of R190(3)(f): A foreign national in possession of a TRV valid for 1 year, who is subsequently issued a four-year SP at a POE, may leave and return to Canada after the expiry of the TRV as long as they have only visited the U.S. or St. Pierre and Miquelon and the SP is still valid.
Not an example of R190(3)(f): A foreign national on a cruise ship departing from the United States and entering international waters would not qualify for the visa exemption. They would require a valid TRV to re-enter Canada.
Upon re-entry, foreign nationals must comply with all other admissibility requirements. If they visit any country other than the ones stated above, they are not TRV-exempt under this provision.