Hi,
If you do this step, it should link with NVIDIA plugins:
cd /usr/lib/aarch64-linux-gnu/gstreamer-1.0/
cp libgstnv* libgstomx.so \
~/gst_1.16.0/out/lib/gstreamer-1.0/
One possibility is the version is not compatible with v1.14.5. The default lib are built with header files of v1.14.5. New version may have updated header files, triggering incompatibility. Please share which version you build for reference.