My dad had a living trust that give me 100% of everything he owned. Found a Merrill Lynch account for $149,000 that my brother took because his name

If your brother's name was on the account, it is legally his. I'm confused as to what you mean "we didn't have time to change it over." After your father's death, there were no options. Even during your father's life, if your brother's name was actually on the account (as opposed to being a beneficiary at your father's death), your father couldn't have changed the account without your brother's agreement. It is possible that your father intended your brother to have that account, and you to have everything else.