As per US embassy website - if you ask for passport back for urgent travel, it will be returned without visa and you cannot resubmit - you have to go via the interview apointment route
Interview Waiver processing takes approximately four to six weeks from the time the application arrives in the Consular Section. Processing times vary and may exceed this timeframe due to staffing and incoming workload. Please plan accordingly.
While the Consular Section is processing your Interview Waiver application you will not have access to your passport and will not be able to engage in international travel. If you request return of your passport prior to the completion of Interview Waiver processing, the Consular Section will not issue your visa prior to returning your passport. Following your emergency travel, you may continue with your visa application by scheduling an in-person appointment.
Visa appointment wait times in Canada currently exceed one year in most visa classifications.
https://ca.usembassy.gov/visas/visa-renewal-by-mail/