Can`t get a good green in Separation Studio

[Rockers]

Please check the attached artwork.
After bringing it into Separation Studio all the green is gone. The green channel contains no data. I can pull the Saturation adjuster all the way up to +100 and it won`t make a change. Now in UltraSeps it`s the total opposite, green overload.
Now what are my options here to get a better result in Separation Studio.
And how would you sep this?
My client insists on 8 colors, but Sep.Studio gives me a maximum of 6 to work with if I generate a brown channel.
Am I`m doomed?

[Sbrem]

This might be a good image for index separations, plus a halftone where it fades off, index breaks down I think at fading to nothing, a halftone there would be more smooth.

Steve