Evangeline resonated with Dyon, connecting with The Seal to seal off the flow of Dyon's thought process. The moment he came close to an answer, before he was strong enough to handle the backlash, he would fall into a state of confusion, causing him to go back to square one.
Dyon wasn't new to using arrays to manipulate the thoughts of others. For example, when he placed a contract seal of Alidor, Alidor was then forced to do everything for the sake of Dyon. However, that method was very crude.
Alidor only followed the laws of the contract seal because not doing so would result in the loss of his life. If Alidor decided he didn't care about his life anymore, he could very well harm Dyon.
However, how could The Seal be on the same level as a crude creation of Dyon's when he was still a mere meridian formation expert? No. Their difference was akin to heaven and earth.
The Seal was capable of predicting, adapting and changing its methods, all with no harm to Dyon at all.