“Marble ball”. Who even says that? Most people just call them marbles. His way of communication is so damn alien.
Russell under- or over-explains things because he's bad at judging what inferences other people are likely to make. Take for example this infelicitous line from one of his emails to Hardin:
You're doing a lot of looking on from the outside and accusing me of stuff without knowing any of the facts and the figurative wrestling I've had to do with the once proposed witnesses.
Any normal human would simply refer to "wrestling I've had to do with the once-proposed witnesses" and leave it at that. They'd know that the reader wouldn't assume they meant
actual wrestling, with people rolling around on the floor in singlets. But, because Russell's sluggish pea-brain grants him little insight into the typical reader's perspective, he says, "Hmm, don't want them to think I was trying to beat up my dad and brother, better qualify it by saying '
figurative wrestling.'"
This is my interpretation, anyway. I think it explains the "largest marble ball in the world" line. Russell says to himself, "It might confuse people if I say, 'The largest marble in the world.' It's not a
real marble, you can't roll it across the floor or anything. I'll qualify it by calling it a 'marble ball,' that's better."
I fear that in all this "Steve" talk we're overlooking my favorite (possibly entirely fictional) Greer Universe friend "Ken" who always encouraged Crusty Rusty in his insane antics and passed along his sage legal wisdom. Where has Ken gone?!
Didn't he die in the ER in the book after the Mexican hitman set fire to him? Or did he recover? It's been too long; I don't remember.