GRN Holding Corp (GRNF)

[e-ore]

They don’t. A PCAOB auditor is required, and they are not current with their SEC filings

"In addition to filing annual reports on Form 10-K and quarterly reports on Form 10-Q, public companies must report certain material corporate events on a more current basis. Form 8-K is the “current report” companies must file with the SEC to announce major events that shareholders should know about."
https://www.sec.gov/fast-answers/answersform8khtm.html

The "major events" companies "must file" include
Dismissal or resignation of registrant's certifying account
Engagement of a new certifying accountant
Departure of officers
Appointment of officers

8ks must be filed within 4 days of the above events