Hi Matt,
I have just tried this scenario with auto call recording turned on:
1. Inbound call to some extension direct number
2. Blind transfer to another extension where the call was sent to voicemail
Actually in this case, when I look at detailed account call log, I can see links to recording and voicemail. 
In simple view (account call log) only recording link presents.
GET https://platform.ringcentral.com/restapi/v1.0/account/255537016/call-log/AZcauPWqp3sDNCM?view=Detailed HTTP/1.1
Accept-Encoding: gzip,deflate
Authorization: Bearer XXXXXXX
Host: platform.ringcentral.com
Connection: Keep-Alive
HTTP/1.1 200 OK
Server: nginx/1.10.2
Date: Sat, 24 Jun 2017 00:26:38 GMT
Content-Type: application/json
Content-Length: 746
Connection: keep-alive
RCRequestId: c97f0a52-5873-11e7-abbe-0050569792e2
RoutingKey: SJC01P07PAS06
Content-Language: en-US
Vary: Accept-Encoding, User-Agent
Content-Encoding: gzip
X-Rate-Limit-Group: heavy
X-Rate-Limit-Limit: 250
X-Rate-Limit-Remaining: 249
X-Rate-Limit-Window: 60
{
  "uri" : "https://platform.ringcentral.com/restapi/v1.0/account/255537016/call-log/AZcauPWqp3sDNCM?view=Detailed",
  "id" : "AZcauPWqp3sDNCM",
  "sessionId" : "19224961016",
  "startTime" : "2017-06-23T23:51:07.906Z",
  "duration" : 40,
  "type" : "Voice",
  "direction" : "Inbound",
  "action" : "Phone Call",
  "result" : "Voicemail",
  "to" : {
    "phoneNumber" : "+1234XXXXXXX"
  },
  "from" : {
    "phoneNumber" : "+1234XXXXXXX",
    "name" : "PLATFORM TEAM",
    "location" : "Akron, OH"
  },
  "recording" : {
    "uri" : "https://platform.ringcentral.com/restapi/v1.0/account/255537016/recording/752813816016",
    "id" : "752813816016",
    "type" : "Automatic",
    "contentUri" : "https://media.ringcentral.com/restapi/v1.0/account/255537016/recording/752813816016/content"
  },
  "transport" : "PSTN",
  "lastModifiedTime" : "2017-06-23T23:51:54.108Z",
  "billing" : {
    "costIncluded" : 0.0,
    "costPurchased" : 0.0
  },
  "legs" : [ {
    "startTime" : "2017-06-23T23:51:07.906Z",
    "duration" : 40,
    "type" : "Voice",
    "direction" : "Inbound",
    "action" : "Phone Call",
    "result" : "Voicemail",
    "to" : {
      "phoneNumber" : "+1234XXXXXXX"
    },
    "from" : {
      "phoneNumber" : "+1234XXXXXXX",
      "name" : "PLATFORM TEAM",
      "location" : "Akron, OH"
    },
    "transport" : "PSTN",
    "billing" : {
      "costIncluded" : 0.0,
      "costPurchased" : 0.0
    },
    "legType" : "Accept"
  }, {
    "startTime" : "2017-06-23T23:51:07.933Z",
    "duration" : 21,
    "type" : "Voice",
    "direction" : "Inbound",
    "action" : "Phone Call",
    "result" : "Accepted",
    "to" : {
      "phoneNumber" : "+1234XXXXXXX",
      "name" : "Kirill Konshin"
    },
    "from" : {
      "phoneNumber" : "+1234XXXXXXX",
      "name" : "PLATFORM TEAM",
      "location" : "Akron, OH"
    },
    "transport" : "PSTN",
    "billing" : { },
    "legType" : "Accept",
    "extension" : {
      "uri" : "https://platform.ringcentral.com/restapi/v1.0/account/255537016/extension/255537016",
      "id" : 255537016
    }
  }, {
    "startTime" : "2017-06-23T23:51:14.177Z",
    "duration" : 13,
    "type" : "Voice",
    "direction" : "Outbound",
    "action" : "FindMe",
    "result" : "Accepted",
    "to" : {
      "phoneNumber" : "+1234XXXXXXX",
      "name" : "Kirill Konshin",
      "location" : "Akron, OH"
    },
    "from" : {
      "phoneNumber" : "+1234XXXXXXX",
      "name" : "Kirill Konshin",
      "device" : {
        "uri" : "https://platform.ringcentral.com/restapi/v1.0/account/255537016/device/91552389016",
        "id" : "91552389016"
      }
    },
    "recording" : {
      "uri" : "https://platform.ringcentral.com/restapi/v1.0/account/255537016/recording/752813816016",
      "id" : "752813816016",
      "type" : "Automatic",
      "contentUri" : "https://media.ringcentral.com/restapi/v1.0/account/255537016/recording/752813816016/content"
    },
    "transport" : "PSTN",
    "billing" : { },
    "legType" : "FindMe",
    "extension" : {
      "uri" : "https://platform.ringcentral.com/restapi/v1.0/account/255537016/extension/255537016",
      "id" : 255537016
    }
  }, {
    "startTime" : "2017-06-23T23:51:29.593Z",
    "duration" : 18,
    "type" : "Voice",
    "direction" : "Inbound",
    "action" : "Phone Call",
    "result" : "Voicemail",
    "to" : {
      "phoneNumber" : "+1234XXXXXXX",
      "name" : "John Smith"
    },
    "from" : {
      "phoneNumber" : "+1234XXXXXXX",
      "name" : "PLATFORM TEAM",
      "location" : "Akron, OH"
    },
    "message" : {
      "uri" : "https://platform.ringcentral.com/restapi/v1.0/account/255537016/extension/256440016/message-store/752813928016",
      "id" : "752813928016",
      "type" : "VoiceMail"
    },
    "transport" : "PSTN",
    "billing" : { },
    "legType" : "Accept",
    "extension" : {
      "uri" : "https://platform.ringcentral.com/restapi/v1.0/account/255537016/extension/256440016",
      "id" : 256440016
    }
  } ]
}