I am travelling to Syria with my family in a couple of months, but I am not getting a straight answer regarding the visa situation. Do my grandparents, who were both born in Syria (and it states that on their Canadian passport) need visas prior to arrival?

We called the embassy in Ottawa, they said they would issue a Free visa but they needed a piece of Syrian ID with the Canadian passport. They grew up and lived in Lebanon before moving to Canada so they do not have any Syrian Issued ID (only lebanese). The embassy they would not issue it for free without the ID. But said they 'should' be able to get one on arrival for free without the ID, but may have problems boarding the flight without one.

They are flying (so would be checking in with AA) DTW-ORD and then BA ORD-LHR then Syrian Arab LHR-DAM. So I am not sure if they will need a visa before or not. Its not cheap (77$ each plus postage)

I couldnt find visa information on the AA website, but on the NWA website it states - Visa not required if:
A. passport states that passenger is born in one of the
following countries:
Algeria, Bahrain, Egypt, Jordan, Kuwait, Lebanon,
Libya, Mauritania, Morocco, Oman, Qatar, Saudi Arabia,
Somalia, Sudan, Syria, Tunisia, United Arab Emirates or
Yemen Rep.

B. being of Syrian origin and holding foreign passport
together with one of the following documents (may be
expired) issued by Syria, which must contain a photo of
the bearer:
- passport; or
- driver's licence; or
- photo ID card.

I'd defer to the Ottawa's consulate's position if they can't prove they are born in Syria (stating so on one's passport may not carry weight with some countries). Otherwise they may be denied embarkation probably at LHR and $77 is a cheap price to avoid that.

Just doing another look on the Syrian embassy website. Looks like they could apply for a new Syrian ID or Birth Certificate through the embassy (for only 6$!). Unfortunately I cannot read Arabic to see what the requirements are.

That'd be a good idea if it can be done quickly enough.

This looks like a viable option if it can be done quickly enough.

Otherwise, I wouldn't leave for Syria without a visa in the passport.