It only concerns new installation of JDownloader. If you had JDownloader installed well before May 6, you're unaffected.
What happened is that the hacker hacked into JDownloader.com (the website) and switch the downloadable installation file with infected file.
This type of attacked happen at every major software, including Linux (the infamous XZ library), Password Manager (most recently, Bitwarden CLI binary was switcheroo), the list is long.
As for the DLC File, the Anime-Sharing only generates DLC from the links that Uploader supplied, on our premise, we have no business with JDownloader.