How can I integrate event check-in process with event registration information I collected via Jotform?

Currently, several volunteers manually confirm all check-in info for participant was collected via the registration form (excel dump). Would like to use Jotform for the check-in process where volunteer can search for participant's name, and bring up their info to confirm if we have everything needed. If not, some action would need to take place. If all is good, then the volunteer needs to update the participant's status to "checked-in" and serve the next person in line.

You can use Spreadsheet to Form widget:

Guide: https://www.jotform.com/help/442-How-to-Use-the-Spreadsheet-to-Form-Widget

The Spreadsheet to Form lets you populate your form fields from an external Excel Sheet. It will pull existing records and display them on your form.

Let us know if this is what you were looking for.

Looking forward to your response.

Thanks.