Perhaps there’s a metallurgist or materials engineer in the house that can shed more light on this, but failure due to thermal shock is a generally a result of rapid cooling (e.g. putting a hot pan in cold water), rather than rapid heating, especially in a household environment. Rapid cooling puts the surface of the object in tension (trying to shrink around an expanded core), and most materials are more likely to fail in tension rather than compression.
As compared to a lot of other materials, cast iron is regarded as has having good thermal shock resistance and is a fairly tough material. A lot of machine components are iron castings. There are a number of types and alloys of cast iron, and the thermal shock resistance varies among them. It’s been a few decades since I was in the metal removal industry, so I’ve forgotten a lot of details. By the way, machining metal can produce some red hot chips, and there is usually a flood of cooling water over the cutting area.
As far as the skillet breaking, I’ll guess that it was a result of previous abuse or a manufacturing defect. I can’t imagine how putting ground beef into it would cause a failure. Deglazing a pan would cause more rapid cooling than that.