I think that they are INTENDED to be in the guard zone. In fact, such a feature is why the Fel-side New Magincia has the potential to be a safe alternative for shopping for those who can't go to Luna, because of their murderer status (as simply being red is not grounds for being guard-whacked anymore, and one would have to steal while there, or deliberately enter combat on NM or in the seas surrounding it, to even GET into the city in a state that the guards could be called in on.
That rule doesn't necessarily apply anymore. After all, there are several areas freely placable that are ENTIRELY in the Ter Mur Royal City Guardzone, E & SE of the gate. In fact, I own one of them on LA, and another has been there almost since the facet opened. Neither are improperly placed.
I do have one question, though. Does the Griselda quest still give a Magincia map for the imp location, and is the location still accessible?