Unfortunately, Kellie Waymire had an undiagnosed heart condition, and died the year this episode aired, at 36. Her last Enterprise appearance was "Two Days and Two Nights". She was also working on other shows and projects, some of those released after her death.
The producers decided to not recast the character. Cutler only made 3 appearances. It feels like she did more though, because she would sometimes be mentioned in dialogue.