Ethical Standards of Competency & Assessment

Please answer the 2 questions for this vignette.
Dr. Thinnice was a psychologist in independent practice who specialized in health psychology and stress-related disorders. Because the combination of a slowed economy and the limitations of managed health care had taken quite a toll on his practice, he decided to seek new ways of diversifying. Because he was friends with Mr. Borge, the chief operating officer of a successful successful pharmaceutical company, he thought this might provide an opportunity to offer his services as an organizational consultant to the company. The pressure of diminishing income prompted him to move ahead on his idea with only a minimum of training in corporate consulting. He had taken a 1-day workshop in management consulting, and thought that he was now ready to begin offering his services in this area. Mr. Borge was enthusiastic about Dr. Thinnice’s offer to work with his firm. Although the company had been successful to date, it had recently suffered in its financial health, and the CEO was considering beginning a round of layoffs. It would be very helpful, Mr. Borge thought, to have the input of a psychologist he could trust about how to assess employees and streamline the layoff process; he envisioned that Dr. Thinnice could work closely with the company’s human resources department in facilitating this reduction in force. Dr. Thinnice was eager to get started. He hastily developed an assessment process consisting of a questionnaire for the employee, a brief structured interview to be carried out by managers, and a checklist appraising recent job performance. His protocol was largely intuitive, based on the stress management training and counseling he had done with clients in his private practice in recent years. He had given a slightly different version of his questionnaire to psychotherapy clients during the previous 2 years, and he felt that this provided good enough validation to proceed ahead. He presented this to the human resources staff for their consideration, stating that he had used this procedure before with good results. The truth was that he had neither empirically validated his technique nor carried out either a pilot study in an organizational setting or done any formal research in this area.
1. What ethical standard(s) is/are relevant in this case?
2. What should he have done to assure his ethical compliance?
This vignette primarily focuses on Standard 2: Competence, from the ethics principles. I am attaching the ethical principle standards that may help with answering/writing this. Please reference the standards in the paper and focus on standard 2 as well.
The website for ethic standards is below:
https://www(dot)apa(dot)org/ethics/code