Hello there, Indigo! Make sure that the items you are missing are written in the CFG file, as well as making sure their files are located in the items folder. The 3D glasses should have a material file, a jpg file and a mesh file. Make sure those are all present in the items folder. Also, is it the elephant buddy item that you are missing?
It also may depend on which version of the items pack you are installing, because there have been multiple releases of the Legendary Items pack which don't have all the same items.
I hope I can help somehow!