While I can certainly see the frustration, I think the best course of action would be to contact admissions about the requirements before making assumptions or getting upset over what may be a misunderstanding. As a current student, we have a few pharmacy students in the class that ended their pharmacy degree early to enter medicine. These individuals had a prior degree that was used for their GPA assessment which fulfills the most senior level 60 ch from one degree program. Although admissions requirements may have changed from when I gained admission, the "rule" has always been that the requirement for undergraduate completion is referring to the completion of an applicants first undergraduate degree (ie. a person cannot apply in their 2nd year of undergrad) and therefore must be completed by July to fulfill the conditional offer. In terms of the Masters/PhD requirement (inc. PT and OT as these are technically masters programs), this is in place because these programs often come with significant research funding/grant attachments that could have a huge impact on the lab/researcher if the student were to leave early and Dal does not have dual programs (MD/PhD).
For the most accurate information, you should always be seeking information from Dalhousie's Academic Calendar which states "Eligibility for admission requires the applicant to have a baccalaureate degree (equivalent to 90-120 credit hours) from an accredited University, which has been completed or is in-progress to be completed by July 1st 2020, prior to the start of the undergraduate medical program. A Masters or PhD degree is not required. Please note, however, if an applicant is enrolled in a graduate studies program at the time of application, an offer of admission is conditional upon the successful completion of the graduate degree by July 31 of the year of entry to medical school."
I urge you to contact admissions to gain clarity but I can assure you this is likely a misunderstanding based on miscommunication. If it turns out that it is indeed a mistake, things will most certainly be rectified for future applicants, but don't fault those who were recently accepted. I can understand the frustration and believe me I had my own hurdles gaining admission to med school but looking back I am happy I got in the year I did and not the years prior. It sounds weird I know and its not meant to discredit any of your frustrations but make the years that you received a rejection or waitlist to make yourself stronger (and this doesn't just have to be another degree).