I will give my two cents if you don't mind.
I think it is a combination of a lot of things but number one is that Zeke is not yet comfortable in his role in the defense. Any sort of doubt or tentativeness costs him position and leverage. He is the quarterback of the defense and at times he seems lost out there. I think it is something that will come with more practice time and game action, but we can't afford to wait too long!
That comes to the second factor, he may be missing another run stopping linebacker to help shoulder the load, as well as, a large presence at defensive tackle to keep pulling guards off of him, allowing him to make the sorts of plays we got used to watching last year.
Am I confident he can get his "mojo" back? You bet! I have a feeling Obie will help address the problems with personnel and Zeke is a smart, veteran player and will work things out before you know it.
Oskee Wee Wee til I die!