Referrals have always been the business
Over more than two decades the same pattern has held: agents send a client, the client is looked after, and the agent sends the next one. That is the whole model, and it only works if every referred client is handled as carefully as a personal one.
It also means the relationship with the referring agent is treated as the primary relationship. You get told what is happening, when it happens, without having to chase it. Your client is not going to be handed to an assistant, and they are not going to come back to you with a complaint.