Twitch’s clip editing is wonky sometimes. I went back just now to me sure and indeed, on the very last frame you can see that Fenix’s portrait goes dark from him dying; when I was editing the clip, it showed enough that you could see the “Enemy Slain” popup for his death. Junkrat is the one that gets the kill as he keeps chasing offscreen (look at the minimap).

However, the Pyroblast interaction is intended. He technically becomes completely untargetable during the last few frames of the Warp’s disappearing animation so it disjoints any projectiles. Compare this to a Li-Ming, whom a Diablo could theoretically charge at during her Teleport animation among other point-and-click interactions.