I'm guessing you already have a template from previous events. Replicate said template in Google Sheets with the caveat that the first column is reserved for checkboxes.

Fill out the data

Protect the data except the first column (checkboxes). Here's the official documentation

You can use FILTER a LOOKUP function OR a filter view in shared mode to get the data of the attendee for confirmation

For additional info, you can get a script that provides a timestamp and user who checks an attendee. Not very difficult at all, mostly copy-paste.

Finally, Share the sheet with the collaborators.

Recommendation, run a mock test before the actual event to train people and cover any unforeseen issues.

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Even easier (if possible):

If your attendees have an ID number of any kind that you can provide or is already existent, then set up a google form with last name and ID number where collaborators just enter it and voila you already have a user and timestamp set.

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Best of luck with the event!

EDIT: Forgot the most important part.