the problem is her husband has already gotten denied visitors visa twice.
Sure it doesn't hurt to apply a third time, but it's farfetched.
Have you guys considered uhm... having the baby in a less dangerous city? You have enough time to save some money and go to –I don't know– Merida, Campeche, Chetumal, etc. Sure you will have to pay for a lot of stuff, but it's not as expensive as you may originally think. A cozy place rents for ~300 CAD/mo, living expenses aren't much, and you get a lot of security and most likely private health care (they will deliver your baby for ~1000 CAD though) on places where, as mikeyvr failed to point out, plenty of 1st world foreigners come to for treatment.
That being said, I doubt your application will last 9 months from now, specially if it's already started. Chances are your husband will be there for the birthday.
Greetings and congratulations!
I may have failed to point out that many foreigners go to Mexico to get treatment but if you want the best treatment is going to cost you and a lot of money , My mother is a nurse in Mexico thats why im familiar with the cost of treatments. Having the baby here in Canada she will save the cost of the treatment in mexico. She could spend the money in taking the baby to his father in Mexico while he waits.
At the end is going to be their decision as couple on what works for them best.
Greetings and congratulations!