The coverage of chain-in-command in this answer is so on point. One could literally follow each sentence to determine the culprit of any issue. Bravo - A+ in troubleshooting.
Sure, but a jury doesn't have to follow the logical chain of events. Look at the recent talcum powder lawsuits. No solid evidence it causes cancer, yet multiple million dollar lawsuits against J&J saying that it did.
If you asked a similar question about who would take the blame if a piece of X-ray equipment was not working properly and caused some form of harm, the liability might fall on the X-ray machine manufacturer who guaranteed a certain level of accuracy, or it might fall on the hospital that procured the (potentially unsafe/certified) equipment. It might also fall on the physician who wasn't following the proper protocol for using the equipment.