WooCommerce WP_Query using tax_query returns no results (0 = 1)

Plugin’s company proposed a solution to go with the wpdb object and write manually the queries…
Kudos to @Sally CJ. You were right in you theory, as the taxonomies are not yet known (or registered) when the script is executed.
I will go with this approach for now, as time is limited, but will try to get back if I find a solution to the initial problem.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)