It's not possible to deliver headers to paths based on query parameters but it is possible to respond with headers on a proxied path.
        /example
          example: scott
        The above should be set in a 
_headers file.
        
/example / 200!
        The above should be set in a 
_redirects file.
        As a result, 
/example and 
/ will serve the same content but the
        
/example path will respond with the header we provided in our 
_headers file.
        Visit 
/example and see for yourself!