Twitch has long time problem with bots selling follows and views. Now say you would have another bot like wizebot, that instantly bans accounts like that off your chat. That works well when you are on twitch only without restream, and you could even throw in chat delay for non-mods so even people in chat will not see it. However the "embed in stream" chat with token, meant for OBS as browser source, still shows the message even in situation when user was insta banned, the message sticks from restream. Perhaps it would be nice to double check for deleted messages and or banned users, perhaps using twitch configured delay or offering such option in settings?
