The operation was planned to take place on the 3rd of the Larcus month that means two days after the banquet. It would have been fine if Elena just punished them on her own or if she just ordered the margrave who was now just like her slave, to arrest them.
That would have been fine but that would be kinda illegal for this country. Again that didn't matter at all to Elena but she still wanted to punish them with regular laws. One could think of this as her whim.
That was why she decided to catch them red handed when they were executing the crime. If that could harm the children or the workers of the orphanage she would obviously not do it but she had confidence in herself that she could protect all of them in any situation. That was why she was going to kinda use the children as baits. She was even going to use the margrave as a witness.
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