On May 15th, the State of Michigan lifted the requirement to wear masks for individuals that are fully vaccinated - sort of. Employers are still subject to follow the same guidelines as before - masks are required for common areas, meetings, shared spaces, and when you cannot maintain six feet of separation. Yes, this requirement applies to all - even the fully vaccinated.
More details at Coronavirus - May 15, 2021 Gatherings and Face Mask Order (michigan.gov).