Linguists will argue that suicide by strict definition requires intent to do away with oneself. Tuinei surely didn't mean to kill himself. Apologists blame teammate Nicky Sualua for failure to rush Tuinei to a hospital when he convulsed and lost consciousness after ingesting heroin. Sualua has a lifetime to regret an inexplicable decision to drive Tuinei home, where Tuinei expired in a parked car in the driveway. But Sualua didn't force the stuff on Tuinei.
Good people make bad decisions.
Drug use increases a high probability that bad things will happen to good people. Tuinei's self-inflicted tragedy fell into that category. No one will ever know. Tuinei's life will remain a treasured memory for family, friends and teammates. He was beloved by one and all.