Hi there,
Thanks for reaching out. Please note that we are limited in the amount of support we can provide for custom development such as this. That being said, I will try to get you pointed in the right direction.
If you take a look at this file, event-tickets/src/Tribe/Attendees_Table.php you can see all of the filters that are available to hook into in the attendees table.
I would start with the ‘tribe_tickets_attendee_table_columns’ filter in the get_table_column method on line 65.
Hope that helps!
Thanks,
Sky