As long as the meta did not have GST_META_TAG_VIDEO_STR set, it should
be transferred. In this case, I would use pad probes to debug, e.g.
after nvv4l2decoder, then nvstreammux and finally nvinfer to find out
which of these tree is responsible. Then you'll have to fix it yourself
or ask NVidia to do so, since these are third party plugins.