Make the Specific Rioter who Deletes your Thread Public

So, there are a few things to address here.

• Rioters don't generally delete threads. To my knowledge, Tamat and/or Pendragon manage(s) a group of external moderators (not Rioters) that handle the actual work of deletion.
• If there is a moderator that makes the wrong judgement more often than not, Riot likely wouldn't keep him/her around for very long.

if their names were displayed that could be solved and dealt with

Accountability is great, but allowing players to rip moderators apart for making a single mistake would not be a healthy solution. I am sure there are internal systems in place that allow Riot to trace actions back to the individuals that performed them, but there's really no reason that needs to be displayed to the community.

I'm normally extremely in favor of openly displayed moderation, but in this particular instance it would likely just result in angry mobs with no real benefit. I do, however, think that the fact threads are completely deleted is unacceptable for simple offenses like posting in the wrong place. This isn't reddit, each board is amalgamated into a greater whole like a normal forum. Reddit pages also generally allow people to communicate directly with the moderators if something seems in error, which is not the case here.