Doubtful any Insurance Company will commence a new client sign up in this situation, and it will only be luck if someone reading this works at an Insurance Company and tests it out that a true answer will come, one way or the other.
The car should have been transferred to you before leaving the Province, either for free being a relative (if a grandson qualifies, I dunno), or sold to you by the Estate for a nominal sum (with even more nominal taxes paid and therefore forget about the car being willed to you). But unless you qualify for a free transfer to a relative, it may be too late for a sale to happen now, with the need for an Ontario safety certificate. Or, perhaps sold 'as is' and then go through the hoops in BC? I haven't looked up the details of these but it should be easy online.