OK. Sawdust mixed with wood glue makes a nearly undetectable paste. In your case, baking powder or soda applied then leveled; hit with a drop of CA glue will fill the divots, but might be barely visible.
Are you saying to fill the hole with baking powder or baking soda and then to drop a little CA glue on top of it?
If yes, I will try this in a hole in a piece of wood first.