I think he is asking if he can excise the four green polyps from the center of the colony. I'd say it's doable, but it isn't worth the trouble you're going to go through to do it.
I'm willing to bet it's sharing a mat with the other zoanthids in that colony, you're going to have to cut around it, and then peel it up, while trying to avoid injuring the others in the colony.
Honestly you're probably going to have better luck fragging off that section with both colored polyps and letting the rest regrow to fill the gap in. I have a small plug of that same kind of zoa (the dark purple skirt with blue/green mouths) that's sharing a mat with a single palythoa that just... keeps... coming... back!
I've actually got a small chunk of LR that's become a paly colony of culls from that one plug. My roundabout point is that these things can regenerate from suprisingly small leftovers.