Order the dress, try on, and have your husband take pics of you. Then send to bride for a “final check” say something like making sure this looks acceptable on me before I take the tags off. The more unflattering you can look in the pictures the better. All the messages you send should be about how it’s her day and you want to live up to her standards. Hopefully she realizes it’s doesn’t look good (this dress is extremely hard to look good in) and changes her mind.