Were the enamels gloss of flats?
It sounds like something called "Self-Lifting/Wrinkling". This can occur if the paint is thinned too much. Another thing that can cause this if you applied a couple coats of paint after the paint started to cure on the model and or during it's cure time. I've seen several articles on this problem. Most say that to avoid this problem is
do not apply any coats after the first 3 hours of the last coat or not till after 48 hours of the last coat.
I don't know if this is what happened to you or not.
Using thinner on the problem area will have no effect on it.
Hmmm...I not sure what to tell you that may help as a quick fix. Since the area affected is in and around small details, fillers seem out of the question.
If I were in your shoes, and this is just my opinion, I would strip the paint off and start again.