RGS operations question

The great photos from the charter last week got me thinking. Would the train with the mid train helper have been set up that way, given the motive power? Where I have seen a 2-8-0 and a Mudhen together on a train, I've seen the little engine in the lead, with the Mudhen either double heading behind the Consol (or say 20) or cut in 6 or 7 cars back.

Come to think of it, I'm not sure I've seen a Mudhen mid train when combined with another smaller engine, only when with another Mudhen.

Not trying to belittle anyone's efforts. I'm amazed at the whole thing. But I am just wondering...