The real message is in your server logs, it's only hidden from the browser. Vercel dashboard → your project → Logs, filter on the time you clicked. Your console.log output is there too. The digest in the browser error matches a line in the logs if there are many.
My blind guess for "works locally, fails on Vercel, admin action": you use SUPABASE_SERVICE_ROLE_KEY in that action and it's only in .env.local, not in Vercel's env vars (or only set for Preview).