Parsing Embedded JSON

Here's a different take on the solution using Tool Slick.

1. Take Set #2 and paste it in the input of JSON Formatter.
2. Select Format Embedded JSON in settings.
3. Click on Format
4. Take Set #1 and paste it in the input of JSON to CSV Converter
5. Copy the subset of output of Set #2:-

   "Criteria1": "50",
   "Criteria2": "10",
   "Criteria3": "John Howard"

6. Paste it in the JSON to CSV Converter inside the object with id "DEF2", below the name property. So that the input becomes:-

   [
       {
           "id": "ABC1",
           "name": "ABC Corp"
       },
       {
           "id": "DEF2",
           "name": "XYZ Corp Pte Ltd.",
           "Criteria1": "50",
           "Criteria2": "10",
           "Criteria3": "John Howard"
       },
       {
           "id": "XYZ3",
           "name": "NSK Kabushiki Gaisha"
       }
   ]

7. Hit Convert

You will get the same output:-

id,name,Criteria1,Criteria2,Criteria3
ABC1,ABC Corp,,,
DEF2,XYZ Corp Pte Ltd.,50,10,John Howard
XYZ3,NSK Kabushiki Gaisha,,,