He was competent and opportunistic though not necessarily diligent.
Onni planned the security reception and response for the Laconian arrival. While cautious, the plan was insufficient. There was no anticipation of anything on the scale of what came through the gates. Despite Bobbie's concerns, Onni was bound by the terms of the Transport Union statutes.
He had a sister in lockup for larceny. When Santiago Singh took over the station as governor, in hopes of currying favor with new government and to barter the release of his sister, Onni informed Singh about the energy dump from the Tempest's magnetar field projector through the ring gates as gamma rays which can cook the crew of ships approaching the gates. Later, Onni is part of a failed plot to assassinate Singh.