So, I had a thought on the last scenes (to include both girls). Earlier Dr. Mosley had hypnotized the MC, and although he knew what was happening while under, he couldn't do anything about it, not that one would under those circumstances. However, it was after that the MC was forced into installing the spyware onto Dr. Mosley's laptop where it seems she kept all of her previous research which would include the "how to" for her hypnosis.
I'm pretty sure that first "session" in her office was unavoidable, unlike the additional therapy sessions, meaning every playthrough has hypnosis. I only bring this up to be clear that everyone had it, and that was also the only session that included her hypnotizing the MC. Also, everyone had to plant the spyware, so everyone potentially gave access to Dennis to see the results of her "experimental therapy" along with all of her information.
The reason I bring up how the MC could tell what was happening but couldn't do anything is because I feel it may explain the personality change in both of the girls. Both would be aware of what is happening but couldn't do anything about it, and don't want it to happen, unlike the MC when he was under.
Given that up until that point mostly all of the secrets between the MC and both girls in the last scene had been flushed out, minus some details, this would put them in a position to be somewhat out of character to make this decision, even if being blackmail, after all of them knowing of the previous blackmails by Dennis. However, if under hypnosis where they can know what is happening and can't stop it, their final comments make sense. Johanna wouldn't want the MC to see this, and Tamara would want help. Perhaps knowing the hypnosis trick is the weapon Dennis was talking about and planning of using on any of the girls as a last ditch effort.
As I have seen in many post before this, if this is blackmail I don't see either of the girls having anything over them or the MC that hasn't been discussed already that would make them think "ok, just rape me and this will all be over". Especially given the knowledge of how Dennis has not let things go. They all broke into his house knowing this act was the only chance to clear the MC from leverage. I don't know about the mindset of the 2 girls at this point, but both must know that if they allowed this to happen it would ruin the MC, and so if whatever Dennis may have on them would have the same effect, both seem like they would rather weather the consequences with him instead of betraying his trust.
Sorry this goes on, but I had a slow night at work and really thought about this, maybe too much. If it's a willing thing either girl is going along with, despite any reasoning they had behind such a decision, I (maybe not the MC) would feel betrayed and no longer interested in them. So, if I am wrong, or maybe like was said this is a dream sequence, then either way I feel this is really good writing for a cliff hanger, or really bad. We won't know until the story picks up again. I think the potential feeling of betrayal makes this a bad type of cliff hanger though, because it doesn't leave me with an anticipation type feeling while wanting to learn "what happens next" but more of a WTF feeling, making me feel annoyed or irritated instead.
If you read it all, sorry it's long, but this idea has me less annoyed and irritated, and that will help me not roll this around in my head for days. Hopefully if this all makes sense it can calm a few others with annoyed feelings as well.