Already listed for Outcast:
A new expansion book, similar to Perils, Judgement & Ruin. Previous discussions: Book of Outcast General Discussion House of Shadow (Delaque) Errors General Discussion House of Faith (Cawdor) Errors General Discussion Hive War (N21 Rulebook) Errors House of Artifice (Van Saar) Errors...
yaktribe.games
As you mention that's when it was first introduced. Sticking to it here implies intention when also considering balance as mentioned by
@Sump Thing. Same change also applied to TP pdf a couple of years ago.
There are several such odd cases where a cost has changed or simply listed as more expensive in gang equipment lists/tables (compared to TP universal cost). I consider all of them to be mistake, as there is explicit intent to have gang discount, but no mention of having higher cost for specific gangs or fighters. If going by RAW, you could pay 10 credits before first battle and then 5 credits afterwards from TP. IMO that's just silly and painful. Also consider Orlock specialict champ (Arms Master) doesn't have sawn-off in his list, but having TP access it is freely available at 5 credits after the first battle.