If you are after more humidity (and frog needs to be moist) have a good sized water source and cover the top (not all the way) and keep eco earth damp. I know FB's like water more but if you had enough water and a cover your humidity should go up. The fogger sounds like more work than necessary eventhough you would disagree. I know your frog likes branches. He can't speak so he can't tell you what he prefers. Just try covering your tank with adequate water source, create some moisture, and you may not need fogger. Maybe the light is drying your moisture and your fogger has to replace it.