i think you need to increase your lighting. i have the same pieces however different color due to which halide i place them under. one under 400watt radium 20k's and the other under 250watt ab 10k.
I did as suggested and I am seeing some come back. I can tell that now its between green and yellow but not there yet. I guess it will get there slowly as with any sps.
i bought a yellow stag and it was yellow under 20k bulbs put it under my t-5s and it is green so im on the same boat. luckly i setup my cube with a 400w radium and it should go back to yellow now lol i think if u have it under a blue bulb it will eventually turn/look green i would put it under a ge 6500k or a 11k bulb.i dont have space in that area so i have it under a blue bulb also.