I went through the booking process until I was given the Documentation Requirements...
"Documentation Requirements
It is your full responsibility and expense to obtain all documents (passport, visas, etc) required by the government authorities in the country of destination. This may vary depending on your citizenship status.
Unaccompanied minors (less than 18 years of age) and single parents travelling with children may require special documentation. Canadian Citizens born in certain countries may require a visa in addition to a valid passport. A permanent resident card will be required for permanent residents/landed immigrants who are not Canadian citizens.
We strongly recommend that you travel with a valid passport and be prepared to present government issued photo identification before boarding a flight. Passports may have to be valid for six months beyond the date of the expected return to Canada.
If you need to know which documents are required, please contact Signature Vacations at 1-866-324-2883 before booking."
Bottom line - passports are a "recommendation" not a requirement.
Furthermore from the websote of the Dominican Embassy in Canada:
"
For Canadian citizens
We recommend that everyone travels with a valid passport; however, Canadian citizens can enter the Dominican Republic with their original birth certificate accompanied by a government issued picture ID (i.e. Drivers License, Health Card). If the person was not born in Canada they can travel with their original citizenship card instead of a birth certificate.
For Permanent Residents of Canada (Landed Immigrants)
To enter the Dominican Republic, all Permanent Residents of Canada must meet hold a valid passport from their country of origin. The requirement for visas and/or tourist card will depend on the country of origin. Please verify the list of Countries of which its citizens can travel with visa, tourist cards or none."
Net result - the same.
Gregg