No need to be so hard on yourself, we're all learning. From here it sounds to me like your boss is trying so hard to pass for White that she had you going there! Why do I say this? Why did she hem and haw in the meeting and then later privately disclose her Mexican / Indigenous heritage?

White-passing Louisiana Creole here...I got relatives ... Some of them could never pass for White ... others fly the confederate flag and get mailings from the KKK! Not saying your boss is like that second bunch, just saying you threw her a good pitch and she missed it.

Learn from this, forgive yourself, and keep on keeping on.