Knowing about the pocket dimension should come in very handy when it comes to using the cerebral inhibitor.
Wells’ invention of the cerebral inhibitor — even though it failed — is at least a sign that Team Flash might get moving on trying to take the Thinker down by using all of their resources.
Hopefully “Subject 9” is a sign that Team Flash will finally put their heads together, use all their resources, and come up with a plan.
At least they did manage to figure out that the Thinker’s lair is tucked away in a pocket dimension in this episode.