Aylam They told you wrong. Thailand elite is a private company, and the people you talk to are sales agents. Anyone can own a company, plenty of people who don't even live in Thailand have ownership stakes in companies in Thailand (real estate, investment and development, e-commerce, ext), it just has to be setup.
You can't work in a field or manner that would require a workpermit, but you can own the company and do work for that company as an owner.