That sutta provides the correct description.
The difference between a dead body and the body of an Arahant in nirodha samapatti is the following:
– The dead body is “really dead.” It does not have a pulse or body temperature; the body becomes cold.
– The physical body of an Arahant in nirodha samapatti does not have a pulse either. But the body temperature is maintained by kammic energy.
That is the description in the sutta.
– But, if one understands the concept of nirodha samapatti, there is no need to look for a sutta.