Airbags set off while car being serviced

Took a 2015 Mitsubishi RVR (Outlander) AWD into a mechanic to have the Airbag Service warning looked at- car had been jump started from a dead battery and the Service warning was flashing.

Somehow they got the airbags to deploy during examining it (BANG), and they’re claiming a faulty module was to blame.

Is it at all possible that a fault in the vehicle would cause this, while it was being serviced, as opposed to an error on the part of the mechanic?