Are you sure that Sherry Marler was profiled on UM? I don't remember seeing it on the show. I started watching the show in March of 1989, so it's possible that UM profiled her case before then, and the case was perhaps never rerun on cable.
Anyway, I found a link. Based on the profile's details, it is current. She was born in 1971, and it says that her current age would be 33 (if she's alive).
http://www.dps.state.al.us/public/ab...276&type=Adult