When I first entered the strip, I got the Victor invite - but nearing the Lucky 38, I saw a dead Victor (?) outside and the securitrons were immediately hostile...

I reloaded a previous save and chose to ignore Lucky 38 for now - but every time I entered there, the securitrons remained hostile. In the meantime I did enter Vault 11 and did what House asked me, prompting the "house always wins, II' quest - but I still can't enter that Lucky 38 without immediate hostilty... What is going on?

Does anybody know how to 'reset' this?

Did you happen to have gone into one of the vaults where they had that suicide chamber?
Word is some of the turrets or robots in there are Lucky38 faction.

Other part is there is nothing in the suicide chamber worth looting.

Yes I was, but didn't shoot the turrets - mind you, they were hostile before I even got near there...

You didn't shoot the turrets? So you just let them kill you?

Same thing happened to me, I was doing quest for House then All of a sudden I went into Lucky 38 and everything hostile. Never figured out the problem just reloaded an old save took the same decisions and everything was OK so no idea what caused the hostility

I have had similar problems with seemling random hostility.
I have not had the problem with 38, but I was in hoover dam when the Quarter master went off on me.
I didnt loose faction for killilng him, so I think he must have been related to the youll know it when it happens quest.
Must be something we triggered with out knowing it.

In the meantime I used the wiki entry for 'dehostilizing' but that caused Mr House not being able to speak to me on the main console wthin the penthouse...

At the end, I couldn't be bothered and went in to kill him

(BTW: you can decharge the turrets with the console within the vault by switching them off)