I have already gone through your troubleshooting post.
We have two sites (One for mobile and the other for desktop). The twitter card meta tags has been added only for mobile site. So, please access the mobile site via mobile compatible view and then do "View page source", then you'll be able to see the meta tags for twitter card (same screenshot shared above).
To access the mobile site, /m after /tienda is important and the browser should be in mobile view. Attaching screenshot for your reference below.