Also, Amu did promise Scavenger that she'd keep their secrets, and while I can see her deciding to let her mother in on those secrets (because it's her mom and she trusts her implicitly), I really can't see her deciding to delegate to her mother's psychic professional acquaintance. Not least because she's kinda quietly freaking out right now, enough that I doubt such an orthogonal solution would be the first option to come to mind.
All that being said, though, I can see you're set in your opinion, and even if I believe it's both OOC for Amu and rather scummy in general, there's nothing I can realistically do to change that.
My friend, "in-character" went out the window the moment Midori Hinamori started haranguing her daughter for the truth like a helicopter parent.
It's quite ironic, really - during the
exact same episode of the series where Saeki helped the Guardians find Ikuto, right before they drove to her TV station, Amu had a phone call with her mother angsting over telling her the truth about what they were about to do (i.e. find Ikuto and potentially fight him). At that time, Nikaidou was driving them around and encouraged Amu to call her parents, because it was getting late and knew they would get worried.
In the end, Amu chickened out of telling them anything and deflected using the excuse that it was "Guardian business" and that Nikaidou was chaperoning them. Midori recognized Amu was hiding thing, but acknowledged that it must be important to her and didn't press Amu or demand she not go (much less send someone else), but only said to Amu that she could tell her the whole story later.
In-character, Midori should have accepted Amu's explanation of having made a promise and not pushed like she's constipated. That vote in 2.1 should've gone through without any dice rolls, if everyone was "in-character". Midori wouldn't even be a problem. Not if things were "normal".
But that didn't happen. That Bane has ratcheted up Midori's fear and concern. She's no longer "in-character".
In-character Amu, I think, would probably do what
@Quickshot0 wants to do and go full-rebel against her mother, refuse to say a word and storm out of the house, leaving her mother aghast and dismayed.
But if we did that, this out-of-character Bane-fuelled Midori is going to be a futher problem down the line, because she's going to have a freak-out at Ami and Tsumugu over Amu's behavior. And even if Amu can continue to shrug her parents off with social combat or something every time they try and corner her, at some point Ami is going to get involved in the whole dispute too.
If Ami runs off with Amu, her parents are probably going to lose it and send JPs after us.
If Ami takes her parents' side - Amu sure won't be able to bulldoze her way through her so easily, unlike Midori and Tsumugu.
Is calling Saeki the first thing Amu would think of canonically? I doubt it. Amu doesn't hold her in much regard or know her especially well, she'd sooner call Nikaidou than Saeki. But canonically, Midori wouldn't be cornering her daughter like this either.
New game? New moves.