Want to add a 3rd ESXi host to an EMC AX4-5 SAN

Hello I'm new to this community and basically just as new to fiber channel arrays.

I have a client that has an EMC AX4-5 with two ESXi host machines connected via fiber channel, where they share storage on a single storage pool. This makes things like vmotion lovely but I'm sure I need to convince nobody of the pleasantly suprising benefits of this sort of configuration.

Now they want to add a 3rd ESXi host server, sharing the same storagepool and all in the same vShphere configuration.

I'll attach pictures of the back side of the SAN for reference.

Now please allow me to reiterate how much of a green neophyte I am when it comes to this kind of tech. I've certainly heard of and and knew of it's existence but this is the first time I've ever actually encountered it in production.

As you can hopefully see from the inserted images, each ESXi host is attached by a fiber pair to a fiber channel card on the server. Every available FC port is in use on the san. I don't know why their are 2 pair to each server (to 2 FC cards attached to a riser on each server (once again, I'm sorry for being such an ignoramus)) but I must assume that's the way it has to be and that I can't just remove one pair from the back of one of the ESXi hosts, plug it into the new server, and expect that to work.

I've learned of the existence of fiber channel switches. Would I require something like that for something like I hope to accomplish? If so, would I be able to plug the exisiting fiber pairs into the switch, and then just attach the 3 esxi hosts into any open ports and expect it to work (assuming I've got the drivers working for the FC card in the new server, but would I need 2 FC cards like the current hosts have?)

I'm sorry for reducing the collective IQ of the community with this one, but I know nothing about any of this and I have no where else to turn for advice/guidance. Any bone you can throw me would be much appreciated.