If you look at the photo you will see that the plastic part has burnt away to the extent that the left hand terminal is not supported at all! It has fallen apart already. Banging it will not help!
That’s brilliant. You are a star. I had tried those two holes before, but there was so much fluff behind them I couldn’t find the screws.
Next problem: It was fairly obvious what had failed; see picture. I think it is called the thermal cut out, rather than the thermostat which looks and...