My father just passed away and left my mother everything in his will... My Fiancée is a co-signer on the business checking account. Considering that there was a will and a co-signer, would the bank still freeze the business checking account. If it helps, we live in NY.

What type of business setup is it? Who would be freezing the accounts?

More details are needed here.

It is a corporation and I guess the bank itself would be the one's to put the freeze on the acct.