Except that according to a few NPCs at this point the Crystal Tower is an already extant location that has been under Mor Dhona for literally ages:

(http://bandofthewhitehawk.enjin.com/...ower-mor-dhona ).

In point of fact it is likely the the entrance will be a place that is visited in an Echo related cutscene by Limsa Lominsans. Or you can just go there if you have the gall. Its a place in Mor Dhona called the Tomb of Xande,