No, spouse will not get open work permit if has visitor visa application approved. Its same case with me. I asked POE officer to issue open work permit for me.(recently in Dec 2023). He said previously they were issuing it for visitor visa holder but now its directly issued only for tie up countries e.g. USA, some euro etc not for India.
Only option in this case is to file new application of OWP/WP from inside or outside Canada.
Outside Canada - applicant has to wait in home/applying country till he/she issues WP document. Or has to come back to home country/applying country when get passport submission request from IRCC.
Inside Canada- she has to file from inside Canada and should be in Canada. No need to go to POE, WP document will be mailed to your address in Canada.
Though you can try asking to POE officer. Its no harm asking them. Finally unofficially they have authority to do it for any country. But above one is official.
