He's just last in the hierarchy because of his OAV and the game isn't going long enough to get to him.
Looked at your team and you have
Darling Long A
Cary, Harris, Honeycutt, Williamson Setup A
Bailes Setup B
In blowouts, Darling and Bailes will be the first two used. Then it will go to the Setup A guys in order of OAV with the lowest first.
In close games, it will start with the Setup A guys, same logic on OAV. Since it's a progressive you have more innings than you need so your bullpen isn't being stretched. He'll be used eventually if the other Setup A guys get tired or a game goes long enough into extras.