So I must confess to being a bit confused here.
In the narrative, Lee is a) riding all alone b) riding with his son and c) sleeping in his tent for the last time.
Tents in those days were quite bulky, so presumably it wasn't strapped to his saddle. How did it get there?
Who is it exactly that pitched the tent?As noted they were unwieldy and heavy. Lee wouldn't have pitched it himself in any case, and his son (are we talking Custis who had been captured at Saylors Creek 3 days before the surrender?) couldn't have done it by himself.
Where was his son when all of these people saw him riding "all alone" without even a body servant or orderly or an escort of any kind.
Lee would have had a lot of gear; clothes, camp desk, papers, all the rest. We know he had an entire wagon on campaigns to carry his personal baggage. Where were his things? We know he didn't just abandon them when he rode off. One would have assumed that the tent and the rest were in his wagon but that doesn't jibe with the story.
How to reconcile these things? One suspects that much of this narrative amounts mostly teary-eyed sentimental rubbish, embellished over time.