He described us as food, and told us that there were many more goblins and hobgoblins without providing any exact number. He overheard where we were planning to go, and we kept him with us at the castle during the night. Yvandir Vythari killed him on day two to ensure that he would not tell the other Portal Goblins where we were going. This was done without consensus, and raised questions about how we planned to handle party leadership, though no consensus was formed on that matter either.
The fact that the goblin was able to speak in common is an unsolved mystery.