She was the one that adopted them into her hut and took care of them like her family, they have been living in peace which was what Elsa was looking for, so she did finally found peace although the peace is already at it's demise.
So, Rose was inside the hut with Elsa making some dinner and discussing when Immaculate dashed into the hut with a dagger in her hand, and her hand was filled with blood as she was panting deeply gazing at Rose with red eyes and angered facial expression.
Elsa was so surprised to see immaculate in that condition and wondered what happened to her that had stained her hands with blood.
"Immaculate, what...? are you okay...? what happened to you?" Elsa said as she tries approaching but Immaculate pushed her aside.
And headed straight to Rose who stated moving backwards in fear.
Elsa was surprised wondering what's going on, she wonders while Immaculate came in with blood in her hands just to confront Rose.
"Immaculate, hold on, what is going on with you? you are scaring me? why are you confronting Rose in that manner?" Elsa asked as she tried to approach Immaculate but Immaculate yelled at her.
"Stay away! stay away please! I have to deal with these backstabber!" Immaculate yelled at Elsa and then faces Rose. 
"She's betrayed us both! you betrayed us you fucking bitch!!" Immaculate yelled at her pointing her dagger at her while Rose was moving backwards in fear.
"I swear I didn't betray you! I don't know what you are talking about" Rose responded with fears written in her voice and she was moving backward with her hands raised up as a sign of surrender.
Immediately she made that statement of hers trying to deny Immaculate's accuser, Immaculate angry approached her and appointed The dagger directly to her neck.
"If you dare try to deny it I will put the dagger on your throat and slip your throat immediately then decompose your body here without anyone noticing you!" Immaculate said pointing the dagger on her neck then Elsa immediately approached them.
She new that if she keep on watching them just like that, Immaculate will end up doing something stupid as she has anger issues.
So Elsa approached and started calming Immaculate down.
"Immaculate, please take it easy! you have to be calming down" Elsa warned but Immaculate wasn't ready to listen to her.
"I am not keeping calm until she confesses! she knows what she did! are you going to talk or should I put the dagger in your throat!!" Immaculate yelled at Rose.
"Confess what..?? Rose can you please tell us what it is so that all this can be over, trust me I am not going to allow her hurt you if you tell us the truth, what is it?" Elsa asked then Rose decided to talk.
"Alright!" Rose said breathing out heavily as Immaculate's dagger was slowly and gently coming directory to her eyes, Immaculate was aiming to blind her eyes first before any other action.
"You should start talking immediately or I will have your eyes pulled out! start talking now!" Immaculate yelled at her.
"The truth is that I didn't betray you... you are my friends and I can't betray you! it wasn't the way you think it was!" Rose spoke with a hurried voice as the dagger was just too close to her eyes already.
Then Immaculate angry pinned The dagger at the side of her head which was on top of the table then grabbed her on her shirt and hit her against the wall.
"Then how was it! tell me! after all the promises you made to us still yet you went there and expose our identities!! what kind of a friend are you! right now our life is at risk because of you! damn you!!" Immaculate yelled at her and pushed to her away and angry really looked away being so bothered about how they are going to escape through this place.
Their identity has already been known by everybody and she was recently encountered by some group of men which was the people she fought that had her hand stained with blood.
So with what just happened to her out there about few minutes ago can say it all that if they ever dare to step their feet out of this hut the people will know them immediately and start attacking them.
But Besides, staying inside this hut doesn't guarantee them safety, because the people might already be looking for them and searching the huts one after the other in the name of looking for her.
"Rose, this was not you that I used to know, if anybody tell me that you will expose us, I will not only doubt the person but try to kill him or her but you surprised me... tell me what immaculate is saying is not true" Elsa said referring to Rose because she was shocked to hear that Rose has exposed them to the people even after all the promise she made to them that she will not expose them.
So while she asked that question, she doesn't want to react because Rose will forever hate her if she reveals her true identity of anger to her that is why she is trying her best to do this with a calm and peaceful manner so that no one will end up being hurt among the three of them because they are all friends.
"I... I... I actually did but not the way you guys are taking it, because I didn't expose your secret to the people" Rose responded to her.
"Then how then did the people knows that I am the one! how did they get to know that it was me that was associated with Princess Diana and now their princess is missing in Diana's name, so do you think they will ever let me escape!" Immaculate yelled at Rose who still stand on her words strongly.
"I swear, I wasn't the one that exposed your true identity to everyone! you are my friend so why would I do that against my best friend?" Rose asked looking at Elsa as they have known each other for long now.
They have lived together before when they were kid so the both of them knows what each other would do and what they wouldn't do and that is exactly why Elsa was so surprised to have heard that Rose exposed to their identity to the people that will kill them.
Having heard from Rose, Immaculate was never ready to believe because Rose is the only one that knows about their true identity in this place but Elsa who knows very well what she can do is beginning to believe her because the Rose she know will never betray her at any cost, even at the point of death.
"So... Rose, since you're not the one that did it can you please give us the name of the person that they did it because we believe that you are the only person that knows our identity, so who then did it if not you?" Elsa asked ready to receive a name.