Blacklisted items

Can you tell me if I am doing this right.

I am trying to blacklist this item:

https://steamcommunity.com/sharedfiles/filedetails/?id=3448849230

It comes from this collection:

https://steamcommunity.com/sharedfiles/filedetails/?id=3451957595

I have the below in my config, but it does not seem to blacklist it. Not sure if a reword of the blacklist logic is needed, but since the system is more dependant on collections, it would be good if we can blacklist stuff if it is in a collection but we don't want that one particular item.

Config snip:

  "Blacklisted Skins (skinID)": [
    3448849230
  ],
  "Blacklisted Items (itemID)": [],
  "Import Skin collections (steam workshop ID)": [
    3451957595,