being in an area that is prone to some horrendous weather events, i am familiar with people/companies that take very large cash withdrawals from their accounts prior to these seasonal events, because cash becomes king when you have no power, water, open banks or other businesses, etc. they use it to pay employees, for supplies, etc, but generally return it when no longer needed. potentially, and this is a big potentially, this could be something like this that perhaps the legitimate cash that was not used was not returned to their account, and they did have a way to secure it at home and they think they need to finally return it. but i think they'd also be able to easily prove if this was the case, and not say "i've just been accumulating it." that just rings all kinds of warning buzzers.
now, being an eternal skeptic, i find this scenario as described hard to believe. people who have that kind of money don't leave it stored, because that earns them nothing. not saying it isn't feasible that something like this could be on the up and up, but i'm 99.99999999999999999% sure this is nothing you want to get engaged in.
oh, and your account agreement should (hopefully) state something along the lines of that you can choose to refuse any deposit, just use that option to refuse it.
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