Using the following framework with 3.5 https://gitlab.com/snopek-games/godot-nakama-webrtc
So RPC works for everything that has to display on the client side through puppetsync and mastersync, i.e I can see the reload animation and shooting animations playing on both players' clients.
What does not work under any circumstance, regardless of combinations of master,puppet,remote,mastersync,puppetsync or remotesync is rpc_id or rpc hit collission. Godot detects it as a self node and won't play ball.
See here, the solution was to reword the error to be more informative, not fix the issue https://github.com/godotengine/godot/issues/27332
After the above linked request was closed we are left with the following
rpcp: RPC "methodname" on yourself is not allowed by selected mode
The mode can be any of the 6, the error either goes away and nothing happens hit detection wise or everyting but the collision detection happens and the error shows.
I know the nodes can see each other and talk to each other because I have bullet marks appearing on the receiving end of the shot and the score goes up if programmed to do so on the getcollider()call. What does not happen is the followup rpcid call which gets errorered out as noted above.