It appears to me that the two bebackpacked individuals are together. The second one loses his backpack in the footage. I assume the first has the first bomb in his backpack.
I've watched the footage a couple of times. I don't see either of them losing their backpacks. What part of the video are you seeing suspect #2 without his backpack?
You know what you're right. Thankfully, I'm not on the investigation team.
A wise man once said: "Assumptions are the mother of all fuck-ups"
lol, I wouldn't go so far as calling the villain in any Steven Seagal movie "a wise man".