Is there a "search" warrant that was sealed? While i have read some comments here saying so, my sense is that those comments are based on a mistaken interchange of the terms "warrant" and "search warrant" with the belief that the two are synonymous (and they aren't).
Maybe I missed something, but my understanding is that what was sealed was the ARREST warrant for Arochi, rather than a search warrant. The arrest warrant would include information pertaining to the broader case, and would justify being kept private if (for example) the arrest included allegations of working with certain others that are still being investigated and have yet to be arrested. You don't want to alert them that you are onto them, by writing out what you think you know of the activities and making it public.
Not sure if this was cleared up but there was a search warrant executed for his house for the first time on the same day he was arrested. Both the search warrant and arrest warrant were sealed.