Lambda function works by itself but not in Step

I am using the following example: https://docs.aws.amazon.com/textract/latest/dg/examples-export-table-csv.html

These work wonderfully when I run them as separate Lambda functions. However, I'm having a hard time with making them Step Functions.

StartDocAnalysis produces the following output:

{
  "Ainput": {
    "Comment": "Insert your JSON here"
  },
  "Aoutput": "42baaa094603ed5f656a8d54a144bfcd29caf1255666e11031b7ac6855b436b8"
}

GetDocAnalysis takes that as input, as such:

def lambda_handler(event, context):
    jobId = event['Aoutput']
    response_blocks = GetResults(jobId, file_name)

When I feed the JSON as input in a test invocation of GetDocAnalysis in Lambda, everything works great. When I run this in Step, StartDocAnalysis runs fine and then GetDocAnalysis produces the following error:

{
  "error": "KeyError",
  "cause": {
    "errorMessage": "'Blocks'",
    "errorType": "KeyError",
    "stackTrace": [
      "  File \"/var/task/lambda_function.py\", line 163, in lambda_handler\n    response_blocks = GetResults(jobId, file_name)\n",
      "  File \"/var/task/lambda_function.py\", line 43, in GetResults\n    blocks = response['Blocks']\n"
    ]
  }
}

I haven't been able to get the Step functions to produce any logging or console printing to tell me what it's actually seeing as input. So I'm stuck.

Edit: See the Task Input for the second Lambda function below.