Watson's decision to hire Clyde and the others was quite straightforward. On the one hand, they were strangers who would very certainly face scrutiny if they entered the City of Steel. If they followed the city's residents, they would have a far lesser chance of being discovered. Plus, they could explore the underground city too.
He could enter the underground city by himself, but he was not familiar with the terrain, so he might fall into a trap. He would have to use his strength to get out, and that would attract too much attention. It was better to familiarize himself with Clyde and the others first. Once he was confident enough, he would go there again by himself.
"That—"
When confronted with Watson's suggestion, the few adventurers there displayed apprehension. They had just recently emerged from the buried city. What would happen if they returned at that time and encountered that bunch of deadly magical animals once more?