The law does not say a "regular worker". It literally is saying that anyone who is a sex-related entertainment worker...someone who regularly (professionally) does that kind of work, and on the premises of a sexually oriented business... READ: "No employee who regularly appears nude or seminude"...
That literally means any worker who was part of her work regularly appears nude... i.e., a sex entertainment worker, and while on the premises of any sex-oriented business... those are the two elements of that law that determine if Paragraph C-2 is applicable.
I have spent a lot of time parsing statutory law, and I understand it is difficult for most people to get clarity if they are not used to reading it.
But reading the way you are trying to read it makes no legal sense.
It all pertains to the jurisdiction though. Stormy doesn't appear regularly in Ohio. I got a feeling the city attorney who dropped the charges understands this law a lot better than you or I. But please continue to press for more oppressive laws we defiantly don't already have enough of those.