The fact is the way "prosecution actually works" is you accuse someone of a generic conspiracy, show some element of the conspiracy was beyond a reasonable doubt true (like drug distribution), and then go to sentencing considering any element by preponderance of the evidence. It's a chilling short-circuiting of justice. Ross wasn't convicted of violent acts beyond a reasonable doubt, he was convicted of a continuing criminal enterprise where a judge thought it was more likely than not involved murder-for-hire.
That is literally the only point the ancestor poster was making: that if you have the means to run, it might not be so cushy a plan to turn yourself in for a non-violent crime, if you're assuming you'll get a sentence of less than 10 years at a reasonably safe low-security prison.
And in this particular case, the interesting point is: even if the prosecution didn't believe they could get a conviction for possible murder-for-hire charges, they somehow still got the desired final outcome: a sentence seemingly harsher than what would fit the crime he actually was convicted of.
(Then again, if your "only" crimes are non-violent/white-collar, maybe it is safe to assume you'll get a cushy prison sentence.)
This happens all the time. It is not unique to Ulbricht, and does not really imply anything about whether the contract killing request did or didn't happen.