The 1st stringer tends to have the general stupid do whatever you want attitude anyhow.
Byoudonin go train off camp for a bit after he lose to Oni.
Irie "1st stringer level" stays in camp to train people.
Tokugawa, another "1st stringer level" also stays behind until he can beat Byoudonin.
Oni also decide to stays in camp to train people, even leaving his title as #1 behind.
Kimijima pretty much takes out #8 player of ALL japan, and he doesn't even get an eye blink.
Tohno just bash around and shot ball at every loser in sight.
Duke was #3, but he doesn't really get like he's in that high of a position. He pretty act like Byoudonin yes man.
If #4 exist, he's stranded in another country although he used to be all hail as part of G10, the "Ultimate Army".
I won't be at all surprise if Shuuji just stays behind because he doesn't like traveling on airplane.
Weak excuse, yes, I agree. But I think this arc as a whole is sloppy writing at best. Although I do think G10 match are rather enjoyable to read.