Brunilda technically lied when she told Mattheus she was physically incapable of going into the temple—really a tomb, to be honest.
After accompanying the kid to the city and escorting him back to the relative safety of the Basilean palace, she went back to the Tellus ancestral hall before sitting down before the entrance, bracketed by the gigantic Corinthian columns.
She recalled how the System, which she could not interact with independently as Mattheus could, had blared with warning windows all over the building. Like a digital, metaphysical version of yellow tape. Caution. Do not enter.
Green cat eyes pierced through the shadows of the long hall, all the way to the end, where a large statue of a woman reclined in resplendent toga-like draping of marble. But, more importantly, she saw the temple for what it was.
A container that housed a not-quite slumbering entity.