1- Before we venture to discuss the date that MC manages that Nicole will accept for the next day (Day 21), it must be taken into account that MC will probably be questioned by his parents as soon as they see him after the beating that Beeman has given him. Most likely, even if he is somewhat recovered thanks to Nicole's care at the motel, as soon as they see him they will want to take him to the hospital and file a complaint with a police station. However, to avoid mentioning the previous robbery he did to Beeman and any details that may uncover his friendship with Abi and his affair with Nicole, he will have to lie to them. However, I don't think that any lie will convince them not to report the beating to the police, and that could cause the date to be shortened more than necessary or even not take place (if I'm not mistaken, it's a date for that MC and Nicole have breakfast together).
On the other hand, in the situation occurred in the last cliffhanger, although as I have already said in previous posts, I very much doubt that Nicole will agree to have sex with her husband. I think, depending on the Nicole corruption points, she will claim a headache or she might mention her suspicions between him and Silvia again, based on her feelings for MC . However, in any case, I think that Silvia will suddenly call her boss and make it impossible for John to fuck his wife. However, I do not rule out the possibility that John brings up her possible relationship with MC, based both on the suspicions that Silvia mentioned to him during the night of Day 17 (after MC finds Nicole at Little Big Pond Beach), and on the talks that occurred on Day 19 (when MC defended Nicole when John spoke ill of her while they were in John's office, and when John gave Nicole that bracelet and then kissed her in front of MC and Silvia). Depending on the Nicole corruption points, she could answer him one way or another, but Silvia's likely call will cause John's attempts to come to nothing.
2- As I've already mentioned, I think she's going to call John, causing his attempt to have sex with his wife to come to nothing. As for where she may have been on Day 20, I think she may have been on her own, reflecting on Malcolm, her relationship with her horrible boss, and what the MC has told her. However, while she seems to collect her debt of gratitude to John for letting herself be a sex toy to him and his agency, I don't think she betrays MC and Nicole, at least not willingly.
3- As for that worker, whose name is Vicky Baker, depending on whether or not MC confessed the truth to John about her, she can be an ally or an enemy to MC. However, what I think of her is not related to the blue folder of MC's parents (whose content I think is due to the fact that one of them has serious health problems or that Hal has possibly been given a new position work involving a move to another city).
4- I think Nicole will admit her true feelings about MC to him in the future, but I doubt if she will in the next part. I think it will all depend on the Nicole corruption points, and that includes what kind of feelings (love, lust, affection, etc) she truly has towards her young lover.
However, I think that she began to have feelings of true affection towards MC when on the night of Day 11 she saw that he unconditionally accepted her past as Nicole Starr, which she herself considered too shameful. However, I think she noticed her true love for him after the chat they had after dinner at Little Big Pond and the subsequent moment of going alone to the beach (Day 17).