I have almost solved it, using a Filter instead of a contextual filter. I understand that I can call the view with Drupal API and set the filter to what I want... that would be similar to a contextual filter. I will try, though still not the most elegant way of solving it. I have tested it and works as I want, but I would like to have it as a contextual filter instead of just a filter. For some reason is not working there.

[![enter image description here][1]][1]


  [1]: https://i.sstatic.net/qKbzq.png