I bet there’s a disclaimer on the bottom that says something like, “this plan may have you arriving at a ride show break or meal a little later than you’d like” or something like that.
To answer your question, I don’t think it would be wise to plan that way. They will not allow you entry after the show has started at Lion King. I’m less worried about going to Tusker right after as you’d be fine or that - the show and the restaurant are just steps apart and even with the mob of people you’ll be there within 5 mins of reservation time.
I would manually move things around.
There is not a way to account for single rider. I would just know that you probably won’t wait that long to ride. But I will also caution you that sometimes SR line takes far longer than you imagine.