Howdy Carlos,
I would love to help you with that.
Once you have reached the cart page you are fully in WooCommerce’s world. Any generic WooCommerce tutorial will apply, the events are just regular products in your Woo cart.
I found this plugin on Google that helps add text to Woo pages. Aside from that you could likely create a Woo theme override like this guide outlines.
Would one of those options work? I wish I knew more about customizing Woo itself. I know next to everything about WooCommerce Tickets, but since I did not help write the main WooCommerce I am less of an expert.
Cheers!
– Brook