Oh that's a hard one Sarah....I love the colors and the white is great!
If it was a large EF , the 5x7 kind, I'd say to cut it I. The middle and do one green and leave one.
Now I do agree that I think the green will help outline the white flower lines...and that could be striking....Hhhmm...I think I am convincing myself to tell you to paint it green. Plus it looks like you were able to get a really good heat embossing so the green will be controlled possibly.
Ps: how did you get such a good heat embossing? My two got EP in places not embossed and the didn't embossed areas that were raised! And I used a brayer...