I think there is a way to do it, but it likely involves custom headers on the initial connection that the load balancer can read to route to the correct origin server.
I imagine the way it might go is that the client would first send an HTTP request to an endpoint that returns routing instructions, and then use that in the custom headers it sends when initiating the WebSocket connection.
I imagine the way it might go is that the client would first send an HTTP request to an endpoint that returns routing instructions, and then use that in the custom headers it sends when initiating the WebSocket connection.
Haven't tried this myself though.