I was actually at the live show but didn't get a chance to make this comment there, hopefully it hasn't already been addressed...
Unfortunately, or fortunately, all the women in the shower scene weren't porn stars. The woman who later gets killed by the mechanical locker is Vanessa Bell Calloway, who by the time Death Spa is released had already been in DOOL, AMC, Webster, 227, and In the Heat of the Night. But most importantly, Coming to America, which actually came out the year before Death Spa. But since Death Spa took forever to get released, hopefully she filmed her part in it before moving on to "bigger" roles.
This may mean that the the casting director for this movie had an eye for talent and black actresses on the rise. He or she cast Karen Parsons (aka Hilary Banks) as a super thirsty gym-goer practically begging for a threesome with Michael and Vanessa Bell Calloway (aka Eddie Murphy's Queen to be) as sassy locker-bait. Clearly underutilized talents. Hahaha.
Check the link for a pic of her close-up in the Death Spa shower scene and part of her entrance in Coming to America.
http://www.blu-ray.com/Vanessa-Bell-Calloway/78608/