Botium with custom payload - DefaultWelcome: bot says undefined

I was trying test my application using botium. I have Generated the convo files by using botium-cli import dialogflow-conversations

I have DefaultWelcome intent which has below payload

{
  "cutomPayload": {
    "card": {
      "description": "Hey there! I’m a bot that can help you troubleshoot issues with UPS. Please enter the model number"
    }
  }
}

and Training phases as below

just going to say hi
heya
hello hi
howdy
hey there
hi there
greetings
hey
long time no see
hello
lovely day isn't it
I greet you
hello again
hi
hello there
a good day

In my convo folder I have DefaultWelcome.convo.txt and DefaultWelcome_input.utterances.txt

DefaultWelcome.convo.txt has

DefaultWelcome

#me
DefaultWelcome_input

#bot
!INCOMPREHENSION

DefaultWelcome_input.utterances.txt has

DefaultWelcome_input
just going to say hi
heya
hello hi
howdy
hey there
hi there
greetings
hey
long time no see
hello
lovely day isn't it
I greet you
hello again
hi
hello there
a good day

I tried to run the

const BotDriver = require('botium-core').BotDriver;

const driver = new BotDriver();

driver.BuildFluent()
  .ReadScripts('convos')
  .Start()
  .RunScripts()
  .Exec().then(() => {
    console.log('READY')
  })
  .catch((err) => {
    console.log('ERROR: ', err)
  });

But unfortunately I got the below output

botium-connector-dialogflow Start called +256ms
  botium-ScriptingProvider Using utterances expansion mode: all +172ms
  botium-Convo DefaultWelcome/Line 6: user says ConvoStep {
  botium-Convo   sender: 'me',
  botium-Convo   channel: null,
  botium-Convo   messageText: 'just going to say hi',
  botium-Convo   sourceData: undefined,
  botium-Convo   stepTag: 'Line 6',
  botium-Convo   not: false } +0ms
  botium-connector-dialogflow UserSays called +175ms
  botium-connector-dialogflow dialogflow request: {
  botium-connector-dialogflow   "session": "projects/joules-test/agent/sessions/defee8a0-4b08-11e9-93e7-fd1394066413",
  botium-connector-dialogflow   "queryInput": {
  botium-connector-dialogflow     "text": {
  botium-connector-dialogflow       "text": "just going to say hi",
  botium-connector-dialogflow       "languageCode": "en-US"
  botium-connector-dialogflow     }
  botium-connector-dialogflow   },
  botium-connector-dialogflow   "queryParams": null
  botium-connector-dialogflow } +0ms
  botium-connector-dialogflow dialogflow response: {
  botium-connector-dialogflow   "responseId": "27545943-441c-487f-9f45-2cd32e833ace",
  botium-connector-dialogflow   "queryResult": {
  botium-connector-dialogflow     "fulfillmentMessages": [
  botium-connector-dialogflow       {
  botium-connector-dialogflow         "platform": "PLATFORM_UNSPECIFIED",
  botium-connector-dialogflow         "payload": {
  botium-connector-dialogflow           "fields": {
  botium-connector-dialogflow             "cutomPayload": {
  botium-connector-dialogflow               "structValue": {
  botium-connector-dialogflow                 "fields": {
  botium-connector-dialogflow                   "card": {
  botium-connector-dialogflow                     "structValue": {
  botium-connector-dialogflow                       "fields": {
  botium-connector-dialogflow                         "description": {
  botium-connector-dialogflow                           "stringValue": "Hey there! I’m a bot that can help you troubleshoot issues with Back-UPS. Please enter your model number",
  botium-connector-dialogflow                           "kind": "stringValue"
  botium-connector-dialogflow                         }
  botium-connector-dialogflow                       }
  botium-connector-dialogflow                     },
  botium-connector-dialogflow                     "kind": "structValue"
  botium-connector-dialogflow                   }
  botium-connector-dialogflow                 }
  botium-connector-dialogflow               },
  botium-connector-dialogflow               "kind": "structValue"
  botium-connector-dialogflow             }
  botium-connector-dialogflow           }
  botium-connector-dialogflow         },
  botium-connector-dialogflow         "message": "payload"
  botium-connector-dialogflow       }

  botium-Convo DefaultWelcome wait for bot null +3s
  botium-BaseContainer WaitBotSays error Error: Queue.pop timeout after 60000
  botium-BaseContainer     at timeoutRequest (/Users/madhavam/joules-botium/node_modules/botium-core/src/helpers/Queue.js:46:18)
  botium-BaseContainer     at Timeout.timeoutCallback [as _onTimeout] (/Users/madhavam/joules-botium/node_modules/async/dist/async.js:4936:13)
  botium-BaseContainer     at ontimeout (timers.js:427:11)
  botium-BaseContainer     at tryOnTimeout (timers.js:289:5)
  botium-BaseContainer     at listOnTimeout (timers.js:252:5)
  botium-BaseContainer     at Timer.processTimers (timers.js:212:10) +0ms
  botium-Convo DefaultWelcome: bot says undefined +1m
ERROR:  Error: DefaultWelcome/Line 8: bot says nothing
    at Object.fail (/Users/mma/joules-botium/node_modules/botium-core/src/scripting/ScriptingProvider.js:50:15)
    at container.WaitBotSays.then (/Users/madhavam/joules-botium/node_modules/botium-core/src/scripting/Convo.js:64:49)

So how to solve this issue? Is there anyway I can able to handle the specific response in the intent?