The fact that you've got such good PC coverage on most of the cheese and the bare spots are yellow (are they wrinkly at all?) suggests to me that you've got the same problem I had. I don't think spraying more will help the PC take hold there. There is also the risk that getting the PC that is already there wet by spraying will hinder its growth (I really don't know if that will take place). The next time I made cams, I took steps to reduce the geo growth--lower humidity, more salt, letting the cheeses dry out well before spraying.