I spent some time yesterday reading Canadian family law. While I am not a lawyer, i want to suggest you spend some time becoming familiar with Section 283, as it could be applied to your situation.
Even without a custody arrangment, canada does have such a thing as parental kidnapping. It is very possible this could be applied to her for moving the kids, but more importantly, to you if you take them back to your province.
Right now, based on what you have written about her responses to your request for custody, the phone calls, and her reaction to you taking them in the past....I would be very careful if i were you.
Personally, i dont believe she is considering your request as much as i believe she is trying to find a way to get the money she seems to want. It feels like a stall tactic to me.
Please understand, around here, kids are the touchy subject. And parenting is more important than ANY marriage. Being a parent and being a spouse are considered two very different things.
Gonna need some help from others...cuz i dont remember the full posting name, but a former poster named Bradley, comes to mind that i think would be beneficial for you to read. Someone will link it.
"Acceptance doesn't mean resignation. It means understanding that something is what it is and there's got to be a way through it."--Michael J. Fox
