The only person who admitted any wrong doing
was Piquet and he didn't even get a slap on the
wrist.I'd imagine he's on the black list now and
rightfully so.
It is true that Flavio never admitted any wrong doing but one of them (I could not remember whether Flavio or Pat) did admit involvement indirectly, by claiming that the idea of crashing was actually suggested by Junior.
If there was no discussion at all on the crashing, the person would not react with a comment that the idea come from Junior.
Furthermore, assuming that Junior did indeed made the suggestion, Flavio could easily tell him off if he does not agree. As a team boss, Flavio had the final say. I am sure if Flavio has objected to the idea, Junior would not go ahead with crashing his car as it will not benefit him in any way.