Lord Kitah
I dont think it is the same. As you said they are different genders. Lord Kitah seems to be an Orrian Noble. I suspect it is just a popular name that is cross gender.
You pretty much answer your own question. They’re not the same. Lord Kitah is a male Orrian noble – most likely one who died during the Cataclysm like most other Orrian risen.
Kitah from Factoins was a female Canthan of the Imperial army (no indication of being a noble) who died in Cantha 300 years prior to the game (and thus the Cataclysm), we can meet her spirit in Tahnnakai Temple.
http://wiki.guildwars.com/wiki/File:Kitah_statue.jpg – how Kitah looked
Lord Kitah’s body is nothing similar. Unless her corpse had a sex change operation and was taken to Orr instead of being buried in Cantha (likely in Tahnnakai Temple as well), it’s beyond unlikely to be the same person.
Different people, same name, that happens quite a lot.
Stop treating GW2 as a single story. Each Season and expansion should be their own story.