I'm no banking expert, but I'm pretty sure no-hold same day withdrawals of that size need much more than that. I wouldn't be surprised if her family has contracted with Bank of America for private banking and family office services, which is usually economical around the $10M assets under management mark (wikipedia says 50M[1] but I've seen lower numbers cited in FatFIRE). In which case the savings and checking figure is essentially nominal, as the wealth is there, but tied up for estate planning (read: tax minimization) purposes; if someone needs money, family offices can set up credit lines. I imagine in that scenario they're basically paying themselves interest.
In any case I doubt any bank is willing to publicly state what the thresholds are in a way anyone could cite, for fear of scammers using that info against them or their clients.
