I had some trouble getting this to work as well I thought I had connected everything correctly but I didn’t see my changes of the room temperature in the data back from the thermiq-mqtt card.
I changed to another cable (I cut the cable to a battery loader of an old broken shaving machine 🙂 ) and made sure I really got it in as deep as I could in all the places.
When I started everything again I instantly saw the room temperature of 20.5°C at the display of my Diplomat Duo Optimum 10. Then my writes to the mqtt topic was reflected in the data as well.