They can close their fans up tight, and when they do, they don't look much like they do when open. If you get a good look, it will appear as though the leg ends in a point, rather than a fan or claw. They may close all their fans at times.. so be sure that's not what happened.
There is also a very small species that can look identical to a bamboo.. Golden Fan shrimp. Atyopsis spinipes is the species. They do not get nearly as big, not much over 1.25 inches.. but the fans are much smaller, and harder to see.
There really aren't any other shrimp in the trade that look much like a Bamboo or Flower shrimp, so if it has the same body colour and longitudinal stripes.. chances are it just had its fans shut tight.
Though it is possible some other shrimp got mixed up with the Bamboos, it should have been pretty obvious from the beginning that it was not the same shrimp. If you can get a pic it will help.