Why are the oral change orders risky?

#4 handwritten pls

A forensic engineer accepts a retainer from an attorney for a plaintiff and receives selected documentation from the attorney. Subsequently the engineer bills for work that includes a review of the case documentation. Still later, because of a disagreement with the attorney, the engineer ceases to perform the work without delivering a report to the attorney and all of the documentation provided earlier. Several months later, the engineer is approached by the defense attorney's in the same case and accepts an assignment to function as an expert for the defense in the same legal dispute. Was it ethical for the engineer to accept the new assignment? OA. Yes. Several months passed before she was approached by the defense attorneys. O B. No. She did not have the consent of all concerned parties. OC. Yes. She returned all moneys paid her. O D. No. She drew no conclusions during her firs review of the material.