This single statement tells me that the person you were speaking with really doesn't know or understand the purpose of a thermostat to regulate a heat source.
You do know that your snake can burrow and I can guarantee that the glass under the substrate is above safe temperatures.
This right here makes me never want to buy or recommend another Zoomed product of any kind. You would think that they would know and understand a little something about reptiles considering it is their main business.......... I cannot believe they would have someone this stupid representing their product.
SMH........