Liu Xi was clearly unaware of the situation that Song Qu was facing at the time. The issue was no longer about whether they didn't want to smooth things over; it was that Yang Xiao was unwilling to let things go.
Previously, Song Qu had considered lowering his head to Yang Xiao, but Yang Xiao had chosen to refuse.
If he didn't continue to call for help, then Yang Xiao would start to deal with them.
With Yang Xiao's strength, there was no way they could withstand his means.
Therefore, even a brute, once his strength reached a certain level, could be terrifying.
Liu Xi had not taken Yang Xiao seriously before, simply because she was unaware of just how powerful Yang Xiao really was.
By the time she realized the extent of Yang Xiao's strength, it was already too late.
Otherwise, the situation wouldn't have escalated to this point.