Hidden Cat Litter Cabinet,Ultra-Large Wooden Enclosed Litter Box Fumiture 2-Door Storage Cabinet 2 Open Drawers 1Air Vents Cat Litter Furniture Fit Most of Litter Box.(Whits, No Drawers)

I would just switch one litter to the new stuff and see which the cats prefer. Maybe try a covered litter or that furniture for litter boxes (there are less expensive models than the one I linked) https://a.co/d/0jcdrWo1