Feanaroc

I have some problems and I am not sure if it is some bug or just something that I am missing.

I got the Vampire Sword from Ulcaster . I checked the sword in case I get the other one but it is okay.I can summon Vault Sentry but it says something about me not being master and attacks me.

I went to Lathander Temple with sword but Kelddath Ormlyr has nothing to say. and The Vault quest does not begin.

In one of my old runs I did this quest. I vaguely remember the Vault being located in some island on a river (it may be completely wrong though I am not sure)

With no quest I am not sure if I can enter the Vault even though I go to the right place.

Is it possible to forcefully get the quest bu changing some global variables?

Or even without quest can I make it like I gained access to Vault and CLUAConsole myself there?