In the beginning, the Qi Family wasn't particularly influential, and coupled with his confidence that he could conceal this fact, he did not kill the midwife.
Even if someone investigated this matter, what he did was reasonable. That's right, Qi Zheng believed his actions were reasonable, so naturally, he wasn't worried about the matter being exposed. In addition, he had Qi Mo enter the estate to prevent Lin Qing from feeling too deeply hurt.
As for Jian Feifei… she had instead wanted to deal with the midwife. However, the midwife was very crafty and did not give Jian Feifei any opportunities. Moreover, Jian Feifei's capabilities weren't powerful enough at that time so the midwife managed to escape. Ultimately, Qi Su had exerted a great amount of effort to locate the midwife.
"Your servant pays her respects to Your Majesty." The midwife walked out while being led by two guards and then knelt before the Emperor and trembled.