Regex to not match if there is a substring

Question

For example:

{ criterion: [  
   {  
      "type":"contact_field",
      "fieldType":"select", // this should match
      "operator":"EQUALTO",
      "value":[  
         {  
            "id":"5767",
            "text":"Health/Human Services"
         }
      ],
      "id":23757,
      "ruleId":22402,
      "minimized":false,
      "field":{  
         "id":"1001-456-4748",
         "type":"radio" // the fieldType should match this field.type
      },
      "conjunction":"OR"
   },
   {  
      "field":{  
         "id":"1001-456-4748",
         "type":"radio" // the `fieldType` above should not match this `field.type` but the one that's in its own criteria.
      }
   }
]

Here I have a json array representing criterion. The purpose is to make sure that fieldType and field.type that we are referencing to belong to the same criteria. I am trying to do this by considering they key conjunction as discriminator since it always occurs at the end of each criteria. (Please let me know if there is a better way by using regex to tell if both the keys fieldType and field.type belong to the same json array index).

Following my approach (of considering the conjunction key here as discriminator), I want to make sure that my regex matches the fieldType and field.type that comes as a pair before conjunction appears. If not, then it shouldn't match.

Things I have already tried before:

1. fieldType\W+select(?:(?!conjunction).){1}field.*type\W+radio$\r?\n?
2. fieldType\W+select.?(?!conjunction).?type\s*"\s*:\s*"\sradio\s"
3. I tried referencing examples provided here