Reading the affidavit, here are my takeaways, as RL obviously didn't pan out as a suspect:
1. The aquarium alibi was probably related to him not being allowed to drive, and he thought it'd come up since he at least suspected the crime had happened in the afternoon.
2. He probably didn't bother with one for the transfer station because it was a much shorter trip that happened before the crime probably occurred.
3. Him being outside on his phone was probably due to being attracted by the search activity going on. Given how close he lived to the crime scene, he couldn't really help being 'in proximity' to it.
4. Given the emphasis on guns and knives, both of those implements were likely involved in some way in the murder. I'd be willing to bet the redaction in paragraph 4 is the word 'sharp'. 'Blunt' would fit too, but there's no request for blunt objects in the rest of the search warrant. Further, given the mention of him carrying a gun in a fanny pack, the video probably indicates the presence of a gun in some way.