Can the RSVP on events+ submit more information?

Hi, my client is a show promoter and wants exhibitors to reserve any number of show floor tables through the RSVP process. He does not want them to prepay, instead follow up with them over the phone.

As it is now: the attendee clicks on "I'm attending", then gets sent to register on the regular WP register/login screen. After that they would have to click on "profile" to enter their name, phone, etc. Now that information does not get transmitted to the promoter. Also I didn't see an option anywhere to check how many units (in this tables) one wants to reserve.

My client is not internet savvy and as it is now would not work for him.

I don't know if there is something in the setup I missed, but the RSVP only submits a user name and email address. It looks like that info gets sent even before a person logs in and fills out their name, etc. Can the person's name, phone and quantity to reserve be added to the initial RSVP?

Thank you for your help.