are you refering to the supracaudal scute?
the growth on marginal and supracaudal scutes will be on the inside eges.
i think by edge you mean the outer edge. it is quite thin on normal baby leos, and it could be unusually thin on your baby. also depends on how hard you are pressing. this thin edge erodes away as they grow.
Yes that is what I am talking about. I was able to get in touch with my friend who is a breeder and told me that is normal.. Thank you for you help J.P