This preview still raises the question of what Maya and the MC saw in Isabella's room, because it could provide the answer to who else is in the hospital. Josy, Jill, and Sage obviously went to the hospital to support Derek. I also strongly suspect it's so Maya can support her brother.
I can very well imagine it's so Patrick will come to the hospital. Maya didn't tell her father about Josy before Christmas dinner, and he won't be too happy to see Josy in the hospital. But it's a public place, and Patrick won't be abusive. This is Maya's chance to tell her father that she's in love with Josy and the MC. Patrick can accept it or leave it. It also puts Maya and Josy's relationship back on track. Why? In EP2, we learn that Josy needs to feel loved more than anything else, and when Maya tells her father in front of Josy that she loves Josy, that's what Josy needs to hear.
What's in the locked room? It will be the realization that Isabella knew Lynette and, consequently, Neil too. Let's review the past EPs.
In EP5, Jill wonders why the room is locked. So, it wasn't locked before. But in EP2, it's locked when the MC first enters Isabella's house. Isabella and the MC already had a conversation in EP1, where Isabella learned that the MC's mother died giving birth to him. Isabella works at the college and could therefore access student data. She probably only locked this door so the MC wouldn't see what's in this room. Jill seems to know, but she just doesn't tell the MC because she doesn't know the context. Jill, for example, doesn't know how Lynette moves out.
It's also worth considering that Isabella and Lynette would be roughly the same age if Lynette were still alive. Isabella and Neil have the same favorite song. I think that's to make it obvious what I'm getting at. The question I had at the end of EP11 was why Maya ran into that room of all places, even though it was unlocked. It reminded me of the conversation between Maya and the MC in EP7. At that point, the MC told Maya about his mother and father. Maya told the MC that she wanted to know more about his mother, and the MC replied that they both wanted to. The MC expressed a wish. At the end of EP11, both are standing in the doorway of the formerly locked room in Isabella's house.
It continues. On the MJ branch at the end of EP9, Josy said after sex, so all three mothers have situations. With the right playstyle, the MC gets to know Maya's and Josy's mothers. So, only one mother remains. The MC gets to know his mother in a limited time frame and reads the diary very slowly. He can even skip the sex part between Lynette and Neil in the diary. I skipped it because I personally don't want to know such details about my parents either. But Derek reads it, and he's Maya's brother. I don't know what's written. But I remember from EP7, Maya wants to know more about the MC's mother. Maya and Derek are siblings, and the MC mentioned it to Maya in EP7 so he, too, wants to know more about his mother. HELLO!!! CHRISTMAS PRESENT!!! You should be careful what you wish for.
What if Maya, Derek, and Isabella worked to grant the MC's wish? The MC only knows a short chapter of his mother's life. But the question arises: what all they found out, especially about what the MC hasn't read yet. Lynette being the mother is a given. But is Neil the father? That's not so obvious. In EP1, we learn from Neil himself that Lynette didn't return to him until after 3, 5, or maybe 7 days. I think it was because Derek intentionally cut off his fingertip because he discovered a mistake or manipulation in the research at the last moment, and he didn't want the MC to receive this Christmas present.
A mistake is a mistake. But what could the manipulation be? We don't know who sent the MC his mother's diary. But we do know one thing: Neil wasn't particularly enthusiastic about it, so the MC would read the diary. It's a diary, and Lynette could have written about those 3, 5, or 7 days of separation from Neil. If Isabella really knew Lynette and Neil, she could know something and manipulate the research so that the MC doesn't learn a truth.
Therefore, I assume it's because Isabella and the MC aren't in the hospital with them, because they really need to talk.
