Casse in central Europe

[Frtigern]

So there was I, Fall of 266 BC, King of the Getai and I send a spy to Eburonum and I see the usual stacks of veteran barbarians but then I see one stack of Casse slingers, led by slinger general Beredos. I thought that was odd, so I keep my spy to see what happens to them, wondering if those slingers are somehow sent from the gods to take Eburonum from the Boii and establish a Casse colony in the middle of central Europe. Well, needless to say they were wiped out the next season, but I did have a chance to start trade relations with them. I am playing EB on ALX.exe, Medium Battles, Hard Campaign. I took a screenshot for those who don't believe me. But why the hell were the Casse so far from home? Was there some historical thing about the Casse ending up there or is it some game bug?