How do fees work with brokerage splits?

First, just as with a regular commission check, you are absolutely right...ALL fees for your services would be paid to your broker, who in turn would pay you.

Although what you are paid and how you are paid it is between you and your broker, it's not uncommon for, if you work for a company that "splits" commissions, your split would be the same whether it was a fee for a service or a regular commission. It would be just like, for example, a rental transaction...sometimes those fees are quite small, but they are still "split" with the brokerage.