cloaks are somewhat complicated.
did you copy the cloakmodel.2da as well?
cloaks as most models are defined by a mesh (mdl), a texture (plt) and an inventory icon (another plt, name starts with icloak).
the models textures and icons can be freely mixed and matched however, which is done with the cloakmodel.2da.
so i would guess you copied all the custom models and textures, but forgot the cloakmodel.2da, which tells the game what to do and how to put them all together