I am strongly against how a child looks determining whether or not they are given a name that reflects their heritage. I am half middle-eastern--although people rarely guess my ethnicity correctly (I mostly get spanish, portuguese, and italian, funny enough)--but that doesn't mean my parents shouldn't have given me a name that reflects my heritage.
I highly prefer
Mai to
Zoe. I think her parents would have made the right decision to go with a name that honors her Vietnamese heritage, or at the very least they could have gone with a French name.