I caused her death?

Once Blake was out of the queen's chamber he used the system's large detection range to follow the 15 elite rank soldier ants at a safe distance.

Following their lead, Blake went through a few more tunnels before reaching an intersection with more than 100 ants.

[The room at the intersection is the main queen's chamber, and Bradly is currently fighting the queen and her knight-rank guards while his team is fending off the ants pouring into the room.] The system gave Blake a description of what was going on.

…

"We are running out mana and there seems to be no end to this, you need to end this quickly!" A member of the Blade's edge adventurer party screamed to Bradly who was currently in a 5 v 1 situation.

From the moment they split up with Blake's team, the Blade's edge adventurer party had seen it as a race to the ant queen. So they had used a lot of spells not only to get here quicker but to get more kills.