I have answered your questions in the ticket #150087 opened with our support team. I will post here my reply so that other forum users might benefit from your question.
You can have one Wowza Load balancer server to act both as a loadbalancing server and client, but you cannot have two different Wowza load balancer servers running at the same time, as the load balancer clients are not able to register to two different load balancer servers.
You can have two different Load Balancer servers running at the same time, located behind a virtual IP, having one of the servers active while the second one will be stand-by. If the active load balancer server fails, the second one will get the virtual IP and all the loadbalancing clients will register to the new load balancer server, as it will have the same IP, the virtual IP, so the load balancer client configuration will stay the same.