Advanced Data Validation HELP NEEDED!

Hello everyone. I have been tasked with creating an excel spreadsheet for use on Excel Online through BOX.

The spreadsheet requires a certain validation entry but I am unable to wrap my head around whether it is possible.

Since the spreadsheet will be accessible to everyone in my company network, one of the things I was tasked with was ensuring that there is a cell, that acts like a "check in" of which the current user can only enter his or her name in the field, any other name or value will spit an error. Is there ANY POSSIBLE WAY to make this work?