Maybe I’m just face-blind or being dense but the photos from the scene of the crime look like a different dude than the ginning hostel check in guy. The jackets and backpacks are different. Although people can have multiple jackets and backpacks. We don’t see much of the shooters face but the eyebrows look different. Although, people can pluck/shave eyebrows. I guess the happy hostel guy would have come forward and been like “WTF?” and “I have an alibi” if it wasn’t him?
If they are the same person they may have two jackets that are very similar but slightly different and two different backpacks. Someone on top of opsec or paranoid having lots of easily changeable looks would make sense. Although ideally you would want different colored jackets. It could also be that the camera quality isn’t good enough for the details in the jacket to show up and they only have two backpacks. It does really look like the two pictures on the right could be someone different with a similar jacket to the two pictures on the left though.
Worst opsec agent ever. “My change of clothes will be… essentially the same outfit, but with a black backpack”