I don't remember reading anything about unlocking the Amber romance. It is still very early in the story so no reason for it to come up yet. But I think Ocean did bring up before that
in general it might be necessary sometimes to pursue at some point
some girl to get the interest of another. For example he hinted that going wild with Bella on her neighbor was a better choice for the Nami romance than just staying with Nami as it makes her realize just how close she is to losing MC and how much he means to her

So I don't know, everything is possible. Seeing Bella means you'd run into Amber more frequently and probably have more meaningful conversations, she's more engaged with you as her patient if you date her daughter, so that should play in favor of her romance. On the other hand stealing her daughter's man should be a no-no, so it could also easily play against MC. You also get to see her frequently as MC's shrink but likewise, there should be professional boundaries preventing her from going anywhere with MC. So no clue what the conditions for her romance are.