1. Nope. No power to shadow ban or remove it. Nor are we ever informed that it has happened, nor why. Usually a user complains that they can't see their stuff, we check, and give them some links to approach the admins
2. Most shadow bans seem to be via algorithm (not human action). And admin do appear to fix erroneous instances. So not really "corrupt" etc there either. Bear in kind that admins have also created a special sub for help/info on shadow banning, where the shadow banned can still post and be seen.