You can enable logger for that activity(view java and copy the logger name), and also while tracing you can check exception option in tracer under Events to trace. If any exception is there then it will get captured with its stack trace.
You can copy that, and use it in the logger setting. This will help capture the steps in activity and you can add debug oLog steps as well in between. What is your expectation here to capture? If a error has a stack it will capture in logs anyway. Else you would need to identify the class and enable logger for them