Hello,
Thanks for your interest.
The payment gateway is setup through the e-Commerce System so in this case WooCommerce and you are correct there can be multiple gateways.
However, all payments go directly to the account connected with payment gateway and you can have only one account per gateway.
There is no feature to pay an event organizer from your site as all the money would go to your account connected to a payment gateway.
Therefore, you could collect all the money and then pay an Event Organizer out of your account, but that payment is done outside of WooCommerce or our Plugin.