Be sure to understand distinction (I believe) of plugin (enabling NDI inside OBS Studio, and the free NewTek NDI tools which allows the operating system to receive the NDI traffic over the network (and then be able to hand them off to whatever, including the plugin)
Some camera vendors (Panasonic, I know for sure) has their own software for NDI traffic and neither the newtek tools, nor the plugin required. I set up Panasonic's virtual USB driver to receive NDI camera traffic, and then added what OBS Studio then saw as a USB connected camera