Hi @Kapil,
As per my understanding, Out arguments will not retain its values in case of an exception.
You can handle the exception in the same workflow and take appropriate steps as mentioned by @ImPratham45
Please find the below posts for details and possible workarounds.
Out argument value after an exception
Also, for checking which activity is throwing the exception you can log exception.Source along with exception.Message to know the exact source and exception message.