Complex sentence: He does consider Vertex to be a high priority target, however, it is obvious that he does not know that Vertex is (or is now) a Spiderbot, and always dismisses the idea.
Split into simpler sentences: He does consider Vertex to be a high priority target though. However, it is obvious that he does not know that Vertex is (or is now) a Spiderbot, and always dismisses the idea.