It was entrapment because federal agents posing as crime bosses were threatening Ross that if he didn't hire the hitman there would be serious consequences. He was manipulated and forced into the position he was in.
What about when his (non-FBI, now-convicted) right-hand-man Roger Thomas Clark convinced him to hire someone for murder?
Surely that can't be entrapment.
"Clark didn't comment on that murder-for-hire conversation—which he at one point claimed had been fabricated by Ulbricht but later conceded was real"