Não estou conseguindo acessar o mailcheck

Fiz todos os passos da aula mas simplesmente ignora o arquivo mailcheck.

Código do mailcheck-config

var campoEmail = document.querySelector('#email');
var sugestao = document.querySelector('#sugestao');
var domains = ['gmail.com', 'aol.com'];
var secondLevelDomains = ['hotmail']
var topLevelDomains = ["com", "net", "org"];

var superStringDistance = function(string1, string2) {
  // a string distance algorithm of your choosing
}

campoEmail.addEventListener('blur', function() {
    Mailcheck.run({
        email: campoEmail.value,
        domains: domains,                       // optional
        topLevelDomains: topLevelDomains,       // optional
        secondLevelDomains: secondLevelDomains, // optional
        distanceFunction: superStringDistance,  // optional
        suggested: function(suggestion) {
            console.log(suggestion.full);
        }
    });
});

Chamando no final do html

</div> <!--fim .dialogNewsletter-->  
    <script src="js/carousel.js"></script>
    <script src="js/inert.js"></script>
    <script src="js/dialog.js"></script>
    <script src="js/validacao.js"></script>
    <script src="js/mailcheck.js"></script>
    <script src="js/mailcheck-config.js"></script>
  </body>
</html>

Trecho do html

<div class="contatoCampo contatoCampo--erro">
              <label for="email">Email: </label>
              <input type="email" id="email" class="contatoCampo--validouErro" placeholder="Email.." required>
              <span id="sugestao" class="contatoCampo-msg contatoCampo-msg--erro"> </span>
</div>