They're thinking that it could have been an Orca that killed and ate it because the temperature changed on the tag. Great Whites can regulate their temperature somewhat too so who the hell knows. The ocean is one of, if not, the most savage place on this planet.
When I transferred out of the Army into the Coast Guard I swam 5km/day, I was a rescue swimmer so I had to stay in top shape, not completing a mission meant you failed or were killed. I'd head out in the morning at daybreak, rain or shine. So anyway, I'd head out one day this pod of dolphins shows up, hangs around, then leaves. This goes on all summer long, they'd meet me and off we'd go, my spirit guides would watch over me. One day as I exited the water there was splashing, I could hear them talking back and forth and the next thing I know there's a dead shark washing up on shore. This shark must have been watching me, a 4m Tiger shark. When I got back to base I called one of the state fisheries people, they sent out a team and collected the shark. They hit it in the side rupturing its liver and it basically bled out.