It is not possible to speculate what charges would be leveled by bank since it all depends on detailed facts of the case. But, from what you have mentioned, it may be a case of misappropriation of money and/or criminal breach of trust and/or cheating.
Generally speaking, you should be in a position to resign (without retirement benefits) before domestic enquiry. However, voluntary retirement (with retirement benefits) may not be permitted. You may better check from your employer.
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