Sponge & PermissionsEx
Issue: Vaults can not tell if a player is an OP
Information: This is a sponge issue as sponge hijacks the /op command and pex blocks the command, telling you to use pex as OP bypasses some permissions.
Solution / Workaround: Admins can run /minecraft:op <username> or Add themselves to OPS.json manually
Special Thanks To: aussiewargod