Connecting External Data Source to Wix Events 'Guest List'

I have created a website for my client that allows guests to register for an event. I need to send out an indemnity form that each registered customer signs prior to the event.

My solution is to send a Docusign (or similar) link to each customer and then manually add labels (eg. Indemnity Signed) to the customers in Wix. Is there a way to automate this process at all?

Any help would be greatly appreciated!

Thanks so much!