Here's part four. Again none of this belongs to me, it was just something I saw on Tumblr that I thought I would share with you. Here's the link to the Tumblr page I saw this from: http://taetaetown.tumblr.com/post/128701680275/bts-i-need-u-prologue-timeline
This is foreshadowing Jin’s death. If you notice, the angle that his car is placed at during the very last scenes, it looks as if he’s parked within the water and all you hear are the sounds of the ocean.
This could very well be how Jin dies. The camera then focuses on the frame of the car, and small drops of water can be seen. This could be from the waves splashing against his car.
Whether Namjoon died within a gas station explosion or he has moved away, Jin is still left alone, and with that, he lets himself be swept away by the water.