I've checked on a map and find that Keltic's marker is just slightly too high
My marker seems to be in the right place. Has there been a fix made since you had posted or do you still see it as being in the wrong place? The Ottawa river divides Quebec and Ontario and Ottawa is just on the south side of the river.
I'm in Ottawa (actually Kanata which is a part of Ottawa) so in the grand scheme of things, with you being in Montreal, we are right next to each other. It's only about 150 km (90 miles).