Suspicion
"About that, the person who tried to kill you was probably wearing a Silver-grade mask. An item of that quality could fool even cultivators." She said as she thought about how absurd that was, but that was the most plausible explanation she had in mind.
Aside from that, it would be impossible for someone to disguise themselves so perfectly unless this enemy had a Physique that gave her an awe-inspiring and rare innate ability.
Lothur 'was' only a mortal, but even people like that could perceive distinctions in the physical appearance of a person trying to impersonate another without high-level items or abilities. So, Viktoria had the impression that this enemy had used a Silver-grade item as the second option was even more unimaginable.
An item could be bought or taken using force. But an ability like that, only by being born with one, could someone have such an advantage.