This article will help you see exactly what data is being send to Billy Grace in a few easy steps (this tutorial uses a chrome browser):
Open the website on which you know the Billy Grace pixel is installed
Open the developer console in your browser
In developer console click on the "network" tab. In the filter type "billy". If you refresh the page you should see several items under name. These are the hits that are being send to Billy Grace.
If you click on an event and then on "Payload", you will be able to see exactly what is being send to Billy Grace. Part of this is also the "ed" field, this is the event data you are sending to Billy Grace.
If you keep the developer console and browse the website, you should see more come in over time (these are all the events being send to Billy Grace). You can use this to see exactly what events - with what data - are being send to Billy Grace and debug any issues you have with custom events. Happy debugging!