if they look fine, and not over watered and there is no sign of gnat.. i would keep them in the humidity bin longer to see if they improve. last yr, i had few issues with some of the cuttings growing nicely only to just die on me. not sure exactly what the issue was. i think the area where i kept them were just too dry, and when i try to compensate by giving more frequent water, it just killed the roots while the leaves and cutting itself was drying out due to lack of humidity. i use "clam shell" set up with bottom of two semi-clear plastic bin. it's tall enough to hold.. tall cuttings and their top till the spring