Think about why we have that rule in place. People without access to major trading websites like bp.tf and outpost have a much harder time selling hats and will often sell for much lower or buy for higher than other traders to get what they want since most people won't trade with them. This means most of their trades are outliers, and that's why we don't want to factor them into our ranges. If the person in question was not banned at the time and had access to these sites, that won't be an issue and it's fine to use.