The guy helping out Metallica in their HQ since 2008 also sings background vocals, plays mandolin and does other things on the last AWMH livestream with Metallica (yes, i bought the tickets and saw it "live").
His name is Avi. He likes oat milk and does not drink coffee because it makes him panic. His fav Metallica songs are: One/FWTBT/Mama Said/Unforgiven/Battery/Whiplash/SOTB
Oh, and he puts cereal before milk

How do I know that? I have a talent for finding some interesting information