Robotic da Vinci hysterectomies are safe procedures, but they are surgery, so they entail the risks inherent in any surgery: reaction to anesthesia, infection, excessive bleeding, damage to other organs inside the abdomen, blood clot formation.
The only real additional risk by using da Vinci’s precision for these procedures is that the surgery may take longer than some other methods. The risk here is that the patient is under anesthesia longer, which is a very minimal risk.