Do I need to enable "Server allocation"on my queue? No, this activates Playfab's own server solution which isn't needed when using Gameye.
Using multiple queues Playfab v2 matchmaking is a general matchmaking queue system. If you want to match with the same game mode, you'll need a queue for that mode. Our example only uses one queue, but it's not hard to add multiple. In our example the queue is a constant, not a parameter in the matchmaking, you can make it a paramater and allow the client to specify it on the API call.