The author has said you can romance Milo and Malcolm individually, but they will still be in a relationship with eachother. I don't know if it's a path they just haven't gotten around to yet like the purely platonic path (I haven't tried it myself, I'm perfectly happy with another rare case of a genuine poly route), but unless they've changed their mind, the option was not removed. Unless you mean cutting Milo and Malcolm apart entirely so it's not even a v-poly; in that case I don't believe there's ever going to be any intention of that