I had four small goniopora frags and one colony that weren't doing great, One looked similar to yours does now, and despite a bit of color/flesh I finally threw in the the towel after a month. I moved the colony and it's done a 180, one of the frags has totally perked back up and the others are doing well - but the two remaining have developed some black spots just along the edges of the skeleton (not sure if they're long for this world or not, either).
My biggest challenge is keeping them upright as some of the reef life is determined to keep knocking them unglued...