Can a Check Be Cashed After Bank Account is Frozen

My mom froze my sisters bank account after her death only later to find out a check from the account (police held personal items that included the check in a sizeable amount). There was no will and will be no probate. Is the check valid if she can explain to the bank what happened (police never gave or told her about the check). There was also no beneficiary on the account .

Can a Check Be Cashed After Bank Account is Frozen