It's a bit unclear why you would go through the mixer at all, if before the start of the process, the bank knows about these funds of yours, and also after everything you plan to show the money to the bank again. In that case, you don't need a mixer at all.
~snip~
There is really no point in using a mixer in this particular case, because if you have legally earned money that is in the bank and you buy crypto-currencies with them, and one day you sell them and return fiat to the same bank account, why put yourself at risk that CEX freezes crypto assets and demands additional evidence?
It seems to me that OP somehow wants to break the connection between fiat - altcoins because he doesn't want fiat to have a connection with what he plans to invest in - maybe the thing is that he can't legally invest in that altcoin/token?