"The district court found by a preponderance of the evidence that Ulbricht commissioned at least five murders in the course of protecting Silk Road's anonymity, a finding that Ulbricht does not challenge in this appeal. Ulbricht does not mention his orders for the commission of those murders until his reply brief. Even there, he does not argue that the district court erred in concluding that he deliberately commissioned those murders; rather, he claims instead only that the murders did not support a life sentence because they did not actually take place. But in evaluating Ulbricht's character and dangerousness, the most relevant points are that he wanted the murders to be committed, he paid for them, and he believed that they had been carried out. The fact that his hired assassin may have defrauded him does not reflect positively on Ulbricht's character. Commissioning the murders significantly justified the life sentence."
Given that Ross, his lawyers, and his mother didn't deny that Ulbricht commissioned the murders in Ross' post-conviction and pre-sentencing letter [3], his appeal [1], nor the recent push for a pardon, I lean towards Ross having commissioned the murders.
[1] Appeals court decision with a good summary of everything: https://casetext.com/case/united-states-v-ulbricht-10
[2] District court judge's denial of request to preclude evidence of murder-for-hire: https://www.docketalarm.com/cases/New_York_Southern_District_Court/1--14-cr-00068/USA_v._Ulbricht/142/
[3] Ulbricht's post-conviction and pre-sentencing letter to the judge: https://freeross.org/wp-content/uploads/2015/05/Ross_Letter_to_Judge_05-22-2015.pdf#page=2
[4] Original indictment: https://www.justice.gov/sites/default/files/usao-sdny/legacy/2015/03/25/US v. Ross Ulbricht Indictment.pdf