My Ghosts aren't too picky, but I've heard of some preferring sticks of a specific thickness. It is possible she doesn't like the sticks offered
My ghosts seem to prefer laying on the 1/4" dowel rods I use on the lid of their terrarium to hold the screen in place. Overall they seem to like laying on branches of about 1/4" or slightly thicker but under 1/2" in diamenter. They also like laying high up in general, near the ceiling whenever possible.
Once I moved a female from her 12"x12"×12" terrarium she shared with another female to a temporary enclosure made from a 8"x12" plastic food jar in an attempt to get her to stop laying on the wooden dowels holding the screen in place because it was such a pain to deconstruct & replace the dowel every time I needed to remove an ooth. The entire time she was in the temporary enclosure, over 6 weeks, she refused to lay despite me putting many different choices of sticks and her favorite 1/4" dowel rods. I gave up and moved her back to her original terrarium. Within 15 minutes of returning her she laid a super long ooth, well over 2 inches in length. Poor girl was exhausted after.
Her terrarium had many plants and hiding spots but she almost always laid on the dowel rods in the lid nearest to the light, I'm guessing because it was slightly warmer there. I use full spectrum fluorescent lights, they don't get very hot but it is about 3 to 5 degrees warmer than room temp (76°F) directly under them. The temporary enclosure had no lighting so it may not have been warm enough for her liking.
I also placed the sticks and dowels vertically or at a steep angle in the temporary enclosure, none were horizontal on the lid like what she had been laying on before. The temp enclosure had plastic walls and no plants, the terrarium had glass walls and lots of live plants with big leaves (she never laid on them, rarely climbed on them.) The terrarium was on a shelf with other terrariums on other shelves but none where they would be directly in sight. The temporary enclosure was placed on a higher shelf within sight of a terrarium containing a twig mantis that was really good at hiding & blending in. Maybe the temp enclosure wasn't private enough for her?
It could be for any of those reasons or a combination of them that a ghost may refuse to lay so your female may not be eggbound. I suggest changing her environment to see if that makes any difference.
