Don't see picture of male but assuming he's a salamander butterfly rose tail.
You don't have to worry about butterfly pattern. You should produce some of them for generations to come.This pattern has nothing to do with white color genes. Maybe white genes will make the pattern white instead of clear.
Second and third female should work in pertaining his color. Not sure how black works though. Depending on type of black, you might get black or irid smudges instead. Melano black females are infertile and super blacks are not really pure black (not sure what makes them).
I'm more concerned about the rose trait. Most rose are genetically deformed - unless you know the breeder or the bettas background. The safest is breeding him to a 4 ray female. But if he is a carrier and produces lots of deformed fry, you will have to cull every single one of them, including the healthy looking ones.
If you love rose, simply breed a pair of 8 rays. Good 8 ray genes will produce lots of roses. But poor genes will only yield few, if any.