RabbitMQ Stomp one central Node or domain based?

We have a server with about 400 instances of an application, each of these instances has its own domain.

We want to set up a RabbitMQ(other server) , also Stomp(websockets) for the Frontend and amqp through the backend application.

We have the option to run Stomp through a central websocket or through domain based Websockets.

The central Websocket is easier to set up and we only have one node, but I am afraid that this will become a bottleneck or cause problems that we have not considered.

Which approach would be better domain specific websockets or a central one and why?

If I have forgotten some information, I will add it.