The color change you describe is typical for an animal moving from blue light to broad spectrum lighting (deep to shallow).
It is certainly easy to miss a molt particularly in a smaller stomatopod. The process takes a few days from when they stop eating through the molt to when they resume feeding, but unless you are keeping track of when the animal feeds, it is easy to miss. Also, they will often completely eat the old molt skin, so you won't see the evidence. One sure sign of a recent molt is color change.
Roy