How can I send a zoom invite that requires RVSP acceptance by invitee?

Are you refering to the "Yes/No/Maybe" attendance confirmation to a meeting that is common for Webex or MS Teams? 

I donot believe that Zoom has this option. 

The panelist can add the invitation to his/her calendar, but cannot confirm his attendance from the calendar directly.

I usually add a message to the invitation to panelists to reply back to the email as a confirmation that they have received their link / login credentials and to confirm attendance.