The USD binaries used in OV are not the binaries on usd.nvidia.com (the latter are built from the unmodified Pixar GitHub source). We are working to align OV’s USD packages with those of a standard Pixar distro, but don’t have a firm date on when that effort will be complete.
To get the nv_usd package used in OV, you can get the Connect Samples from Launcher. Building those samples will download the nv_usd artifacts, which you can use to compile your schema.
Hope that helps; sorry for the confusion.