Luna is fully compliant!
Luna has Apollo.io as an integration partner for leads. Apollo obtained all contact information legitimately. Simply because the information was publicly available on the Internet (read: not scraped from LinkedIn which is not allowed, for example).
The rules are that you can only reach out to people in a business environment (hence the business emails) and if there should be a legitimate interest. Basic email automation tools are not GDPR compliant, as they are blasting template message to a huge group of people. Luna evaluates every lead individually, and the AI only suggests a lead when it believes the legitimate interest is there. So, nothing to worry about!