Hi Javier,
I suggest you use RGU mechanism with software flag to do it. It should be designed based on the customer's application. This idea comes from the below descriptions in UM:

The key idea of this way is to determine the reset causes with the different values of a flag variable. It requires to determine the WDT reset by eliminating other much reset sources. See the details of all possible reset sources from UM as following:

For more information, see user manual Chapter 15 Reset Generation Unit.
Have a great day,
Jun Zhang
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