@Vasqueztion If you would just take in account that he was gone for a month, he could be given any information and choose not to second guess it because it is just as such.
Though since it wasn't mentioned anywhere that he has it, it could be that he's just placing the blame instinctively or perhaps there was a previous happening where someone tried to steal the sword and the sword pulled the thief towards the hero.
Also... 5 man party with a cursed hero, a drunk magician, an addicted martial artist, a suicidal priest and a inferiority complex swordsman...
I haven't seen a all male hero party since the 10 years later hero's party after the healer got knocked up by the prince?king? of that party before they challenged the portal... Or maybe the immortal 3 person party that went after the hiddenX#? boss and let the girls leave because they were getting close to 30 and the girls started thinking that they want to get married before they become old crones...