With API Gateway trigger v1 on the lambda instrumentation the following happens, if the instrumented code does not explicitly set the status code on the response object:

• The statusCode variable is an Integer object on the APIGatewayProxyResponseEvent(used with API Gateway v1 triggers)
• this statusCode is not initialized properly with the constructor of APIGatewayProxyResponseEvent
• thus, if the instrumented code does not set the statusCode explicitly, then the value is null
• the lambda instrumentation then fails with a NPE at this stage