Thank you for posting your experience. It's clear that you have resolved the issue of the inheritance of your non-immigration accounts by making your Administrator a co-signer on those accounts. It's not clear to me, however, what will happen to your 800,000 immigration account after you die.
Which of these two interpretations is correct according to your discussions with your bank?
A. Your bank will not allow the administrator named in your will to access the 800,000 because he is not a co-signer on that account.
B. Your bank will allow the administrator named in your will to access the 800,000 because you have made him a co-signer of your other accounts.
Your response will help me understand this confusing situation.