This is actually correct. Explanation and Spoiler below (i.e., stop reading now if you don't want to know more, or scroll down if you do want to know more).
As you know from his story, Ted Sapsen doesn't "move on" with his (after)life like the other bears do by the ends of their stories. As a result, he doesn't undergo the same color and behavior changes that the other bears do when they move on (a.k.a., "ascend"). This is intentional. Of the initial 17 bears and the 4 bears in the New Neighbears DLC, only Ted Sapsen is written this way—all other bears should ascend and change appropriately.
Likewise, the area around Ted won't be permanently colored even if you complete his storyline. Permanent coloration of an area occurs when a bear ascends, and Ted doesn't ascend.
It is a known issue that Ted speaks with ascended speech when giving quests after his storyline is finished. This should be fixed in version 2.3.0.