I was under the impression that was indeed Vorax-Hûl from Chapter 9; it would make sense that the dragon which helped Ragesia conquer Gate Pass would take up residence in the clock tower. As far as the "bat-like wings" phrase, I think that was simply to impress upon the players the sheer exotic nature of dragons, since their characters would almost certainly never have seen one, at that early point in their careers. The wings looked like a bat's, because it's the only frame of reference they probably have (outside of any experience with the Ragesian military and their wyvern riders).