While there is a temperature sensor inside the LSM9DSO, unfortunately there isn't enough information provided in the datasheet to properly interpret or convert the values.  We've made our best guess at interpreting the data, but you may need to incorporate an external temperature sensor if you require accurate temperature values in your system.

This is a known and long-standing issue with this sensor (example), and to our knowledge ST has never addressed it or provided the extra information needed to accurately interpret the raw temperature data.