Hmmm, thinking back to my days as a football referee, I think it depends which force sent the ball into the end zone. If it's a kick, that's a touchback. If the QB drops back in the end zone and is sacked, that's a safety.
In this case the game engine must be ruling that Miami stripping the ball at the goal line is what propelled it into the end zone, where Miami recovered the live ball. Miami in possession in the end zone they are defending as a result of Miami sending the ball into the end zone...safety.
Had the fumble itself (rather than the strip) or a bat by a Jacksonville player been the cause of the ball going into the end zone it would be a touchback.
Of course...I have no idea whether the sim considers force in a situation like this, but IRL that's what would matter.
