Hi Ernest,
How strange, I can see the pages without problems. Can you try to change the browser language to Spanish? It may be an hosting security.
I have tried all your tips, but I do not see the products related to each user appear in the search engine.
The author are normal WP users, they are “post / product” author.
What I don’t understand is that when I search for a product under the title the author appears correctly, but when searching for the author it does not relate the products.
Here you can go to the back office if you need it:
https://literalbcn.com/inicio-sessio/
I attach some explanatory images to understand what I want to achieve.
Thanks