I attempted to complete the triumph with Breakneck, Trust & 21% Delirium but it did not complete; upon further research players have stated that because the weapons were created after the triumph was made they do not work for the triumph despite being pinnacle gambit quest rewards. This seems to be an oversight as I doubt that anyone would argue that I wasn't using gambit weapons, and players like myself who weren't aware that weapons created after the triumph was created do not count towards completing the triumph will end up being confused as to why it isn't completing. I guess adding either a section detailing the eligible weapons to the triumph or making the triumph correctly accept all currently existing gambit weapons as eligible would be a reasonably solution to this bug.