Physician Zeng didn't care whether there were serious injuries or not, what he cared about was the promise of fine wine from Ling Hua. With a good drink, he was naturally willing to run errands and work for her. Whoever she said to save, as long as there was a breath left, he could bring them back to life.
Moreover, the poison used on the person lying on the couch was his own handiwork.
Still, he had to play along with Ling Hua and Xiao Zhen, putting on a show of treating Xiao Zhen, pretending it was a difficult task, and unnerving everyone involved.
After a thorough examination, Physician Zeng looked over Xiao Zhen's injuries, turned to the Emperor with a bow, and declared, "He can be treated and the poison can be detoxified, but it will be cumbersome. I'm afraid it might take a month or two to fully cleanse the poison from his body."
This was the timeline Ling Hua had already laid out.