Custom Variables

Hi all I am new to Contact Center, I am trying to understand the hand-off of variables from ZVA (Voice) to Contact Center. In my current config the ZVA has a skill that is collecting specific user info from the caller (name, email, company-id, extension) when they ask to speak to a live agent. I have the custom fields saved to global variables. I also can see the custom variables I created in ZVA in the Contact Center variables. I have strict instructions for the agent to respond back and confirm the variables are populated with the caller info provided. I created another skill for the agent to run /transfer_to_live_agent. When the call transfers to the agent, I do not see any of my custom variables when the agent accepts the call. I have double checked that my variables are set to global, active setting for Display in Zoom Contact Center client, Display Location is both incoming notification and engagement details. What’s the trick to get the details in the Contact Center Agent workspace?