Dear Roy,
First allow me to share with you the UCCX Administration Guide
http://www.cisco.com/c/dam/en/us/td/docs/voice_ip_comm/cust_contact/contact_center/crs/express_8_5/configuration/guide/uccx851ag.pdf
From here you need to focus on the 2 methods to deliver calls to agents,
Resource Groups or Skill based.
Based on your concern, it seems to be that your set up is using skill based, and this particular agent that you are mentioning seems to have higher skills than the rest, please check documentation section "Configuring Agents"
The way you distributed calls across your agents is not that easy to answer because depends the way the system was set up for you, but I hope you have an idea and where to look on UCCX for now.
I hope this helps
Daniel Amador