So Cait gave me the speech to visit the vault to cure her for her addiction but it didnt activate the mission. Thinking that i would receive in in future prompts i went ahead in the game. I didnt realise it until i googled about the bug. Is there a way to work around this. I would very much like to complete the game with all available perks.

I just did that mission yesterday with no issues. What's the bug?

After i agreed to help her the quest did not activate. So basically i went to the vault and reached the room but nothing happens.

Same thing happened to me today. I didn't think about checking and activating the quest. I just went to vault 95, killed everyone, got her to sit in the chair, tried to activate the detox. I the message saying there is no one in the chair.