Some posts above these, you said that someone moving countries won't change their way of thinking regardless of how many years they live in their new country because the way they were raised will be there forever.
And now you want three ladies (+Eileen, who I don't know what has to do with your ramble) to change their mindset in three weeks (the first of the relationships was open with Samantha after the MC was home for almost a week). It's not coherent, right?
Let me explain it:
The characters aren't perfect, and they have flaws.
Simone and Samantha (and Jamaal to a lesser extent) have a survival mindset, in which they have to do everything on their own. It worked for them for years. They could have asked their friends for loans (Martha and Norah would be there for them) and save on bank interest, but they didn't. They didn't want charity, regardless of where it came from. They won't change that mindset in three weeks or three months.
Family is NOT an investment. Family is a matter of care and love. NO ONE (not Amanda and not the MC) is thinking about the economic benefits of paying for Simone's scholarship. They are willing to pay for it so Simone can fulfill her dream. With a billion-dollar company, they don't need whatever income Simone can get as a coach.
Kiara's attitude is logical. She's used to not having self-esteem, and she doesn't want to be a bother for Norah (and she knows she should leave the house when the new students arrive). She thinks (Solomon has engraved it in her brain for years) that she has no worth by herself, so she wants to live independently now that she will own a house for herself. Moving to the family house was temporary since the start because of a problem. The problem is now solved, and she can return to her house (leaving what has become her home in the interim). Kiara discusses it with Norah BECAUSE she's living at Norah's house.
I don't know what Eileen does in your ramble. She's the one pressuring Kiara to stay at Norah's home.
I don't know where you are from (or what culture you were raised in), but the game is set in a Western culture setting, where women are independent and their lives don't revolve around a man's dick. Men with "strong hand" for their girls are considered part of the problem in that setting, not of the solution. Have you heard about toxic masculinity? Solomon is the example, and I don't want the MC to become like him. The MC is dating the girls, not dictating what they should do with their lives, where they should live, or what they should wear. He proposes, not imposes. It's California, not Taliban-Afghanistan.