"we need to talk right now"
When companions wants to talk "right now" they just get huge yellow "!" marker abowe their head ...
So ... that is kinda allready there.
And some of the things that your companions want to say don't make any sense at all for them to wait; certainly not until nighttime. Wyll should be furious when you agree to help Minthara - not after you finish killing all of the tieflings. He should ask you right away (or once Minthara is out of earshot) what your intentions are and, if you say that you're going to help Minthara, immediately leave the group, warn the tieflings, and fight on their side. You could tell him that you're actually planning to betray Minthara (which might involve a persuasion or deception check, depending on your intention) and then he'd play along. Even if that conversation didn't happen right then - if he's there when you turn on the tieflings, there's a high chance that he turns on you and joins them. Waiting until you're at the party afterwards feels incredibly wrong.
This is completely different matter ...
We are talking here about dialogues that ARE happening in camp.
