Disconnecting the shield ground often requires entry to a restricted area, or an approach within the hazardous area of the associated high voltage.
I don't know of any instances that fit your specific scenario, but the possibility of death or injury is quite high if a shield ground connection is cut.
Within the last year or so, someone posted a picture on this site. It was the burned body of a thief who had just cut the grounding cable of a large transformer.
I have seen documentation on several accidents caused by ground currents and voltages on inadvertently cut ground connections.
On a small system, the hazard of an open ground connection may be negligible. On a large system there will be potentially lethal potentials if a shield ground is opened. Single conductor cables are much worse than three conductor cables.
Under fault conditions, or if a cables is starting to break down, the hazard is much worse.
Bill
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"Why not the best?"
Jimmy Carter
It's certainly possible if a remote fault occurs during this process. The shield wire voltage can rise above local earth potential where the person is standing.
