What do you mean with similar issue?
If you like to test external connection then you could setup a MQTT broker on internet and verify with a MQTT client that your mcGateway is sending to broker.

The code against IFTTT does work, if your spreadsheet not update then verify IFTTT Key and that IFTTT has permission to write to your Google drive account.

If you want to verify your IFTTT account then you could send me your key and recipe name in an PM and I will test against your account from one of my mcModules.