I'm interested in becoming vetted and verified by board admins - to offer various services (reviews, escrow etc.) . can someone advise the process? (if one exists)
As others have said, there is none. Escrowers usually just build up their rep by doing trades and become naturally trustworthy over time. I suggested doing more trades and being more active on the forums. There's already a fair few escrowers too, so it's already a gamble taking a risk with a newer agent.