He didn't have to beat Reinoso and he knew it. That is part of the story. He knew that as long as he wasn't pinned, he would advance.
Also the pools were random and could all be studs. JB never had to deal with the pool system. With a straight line bracket, he might not ever have to wrestle Reinoso.
What was Smith's other pool loss?
PS and the more I think of it, Reinoso had a pool loss before he wrestled Smith. In today's system, he wouldn't have made it Smith.