Ok, so that flow works because the mlx-sensor node it uses creates a message containing object and ambient as properties.
You have a different message coming from the DHT node - so you need to understand the structure of that message and identify what properties are the ones you want to send to Thingspeak.
From the other thread, you did share a picture showing the Debug output for the node - MQTT.FX Thingspeak
It appears you have msg.payload as the temperature reading and msg.humidty as the humidity.
So a starting point would be to replace msg.payload.object with msg.payload and replace msg.payload.ambient with msg.humidity in your Function node.
