There is another thread entitled “DC OR Dick check” http://blog.sherisranch.com/forums/topic/dc-or-dick-check/#post-11521 where a man stated he’s afflicted with “Pearly penile papules” http://www.soc.ucsb.edu/sexinfo/article/pearly-penile-papules, and he failed a DC because the condition resembled genital warts.
All I can say is that Courtesans are trained to distinguish STD visual signs during the DC, and they don’t categorically classify any abnormality as an STD. It might be beneficial to carry a physician’s diagnosis and a legitimate article including photos in an attempt to provide insight into Fordyce Spots or pearly penile papules. However, a Courtesan would still have to proceed with caution, and fail a client on their DC if she has any doubt they have a STD. A Courtesan can’t take any chances concerning a suspected or probable STD.