It is possible, in certain conditions, as can said, for the oil to take off just from the heater coming back on. That would take a long power outage, more than just a few minutes.
If the machine was started the moment the oil temp lockout let it, the compressor could be spun up with so much refrigerant in the oil that there could be very serious damage. The oil would really take off in a hurry if it saw an inverted cold start. That's why the man says 24 hours heat up on a cold compressor.
Let's hope that the noise was just normal centrifugal noise, and that they just need to get the oil back.