How long has it been that way?
My goni closes up for no reason all the time, but it comes out again a little later.
Did you ever upgrade your lighting? IIRC, the last time you mentioned it you were only using NO lighting on your tank... that could definitely be contributing to it's demise.
I had mine under 220w of PC lights and it still wasn't as happy as it could have been (it started turning more red like yours). Since I've added the halide it is regaining more of its zooxanthellae and looking much better and much more yellow.
I also have it in a moderate current area where it gets blown around a bit at times (wavetimer) which it seems to like.
There's still too many unknowns with the goni that don't make it a good candidate for long-term success, but it seems to be hit or miss with most people. I saw a post where the poster not only had long-term success with his goni, but it had sprouted some daughter colonies as well... now if we could only figure out what he was doing right.
Hope it turns out well.