Beneficiary of life insurance

I am not admitted in Florida.  I urge you not to do anything that would be in violation of your duties as executor.

The insurance policy is a contract and you need to take it to an attorney in your area to read as to what to do for his half.  In any event, the insurance company is not going to pay out the money to anyone other that your brother without a court order.  And the court will not release the funds to you unless, I believe, you prove your brother is dead and you are the sole beneficiary of his estate.

You should ask the insurance company if they wish to interplead the funds in to court for the benefit of your brother because you do not know where he is.  They will tell you what you need to do. But you can not and should not take his half.  You could be liable for a crime.