Honestly, her being a zombie at this point should clear all suspicion of murder, there's no need to even consider why the knife is stabbed or why the shoes are lined up.
It's just way too unbelievable that she'd kill someone only to have them turn into a zombie and almost kill her back, you'd obviously assume she turned on her own, that is even what happened and there's nobody there to frame her so no evidence to claim otherwise.
The only suspicious part why they ware both there, though that is quite a big one.
Now if this girl was a known killer of humans and zombies with muscles and confidence to murder again, maybe suspicion would make more sense. Oh also if she wasn't almost being murdered by a single newly turned little girl zombie.