I guess it is about the usual time moderators take to review cases? (We just ended a Christmas season, btw)
I have noticed it may take some time to give a look on individual cases of bans and appeals, and I don't blame them, moderation work can be harsh.
There is also a little chance that whoever is in charge on this case in particular believes the red tags are enough of a punishment, in the end, even if he was banned, nothing would stop a banned user to use a new alt account.
I see more sense in the first part of what you say than in the second. The red tags don't depend on his repeated plagiarism, which is cause for banning and for which he was effectively banned in the past and for having used alts while banned, which is another cause for banning.
On the other hand, if we were to take into account the argument that they can always create alts, no one would ever be banned in the first place, as they can create alts, right?
Some are so dumb that they use the same IP, the same addresses or show other evidence that makes it easy to catch them.
I just feel @hilariousandco is taking his sweet lil time before he'd do the needful.
Let's hope so.