I just received confirmation from some people that the Xbox 360/Xbox One servers for Arkham Origins Online has been retired.  :'(  This Error 3 message does show up every time when the connection fails to load a lobby that can be resolved by simply trying again but I guess it really has been retired this time when it was supposed to be on December 4, 2016 along with PS3 and PC.  At first it only retired on PC for an unknown reason and now it has been retired for Xbox 360/Xbox One for an unknown reason as well.  As of now, the PS3/PS4 servers are still active and I've always played it on there so I'm always available to play with you guys!  As my name shows, my gamer tag is This_Drummer  :)  

If you don't own a PS3 but own a PS4, you can play Arkham Origins including the multiplayer via PlayStation Now.  PlayStation Now is a streaming service for PS4 to play PS3 games.  That's the PS4's way of backwards compatibility.  More information can be found here: https://store.playstation.com/en-us/grid/STORE-MSF77008-PSNOWSUBSCRIBEG/1