i would probably take it to a specialist dry cleaner or if you really wanna do it yourself i would try some sort of OMS (ODOURLESS MINERAL SPIRIT) but before you go splashing it all over so to speak you MUST pre test the dress with the chemical in an inconspicuas area so you know that it will not damage the dress and also do not saturate the dress with the product apply it to a terry towel
me myself i would go for option 1 and take it somewhere