Directors of companies are held responsible for the decisions they made. Delegating that decision to others does not abrogate their responsibilities.
If you are in the SEO industry, please stop hiding behind this. The SEO industry have had ample time and patience to clean itself up (naming and shaming these unethical SEO consultant for starters, offering up material small businesses and mom-and-pop operators, checklists in hiring an ethical SEO practitioner, checklists of methods/practices that should be avoided. How to write up clear statements of work).