I'm with bogertophis on this, lying isn't good of course, but any bad press that can be avoided here is good. Renting and reptiles is already hard enough without adding to it. Especially for something only peripherally related to an animal and not a result of a required care need of the animal. Thawing can be done in water in bags, so a fire hazard is nonexistent for many other keepers. (I.e. not directly caused by the animal. The snake did not pee and cause burns to the floor. No cat scratching up baseboards)
Maybe just say you had a heating lamp to thaw something out, could've been some frozen meat or frozen bread, (omit saying rodent) and accidentally set it down flat with it still turned on when the doorbell rang/people arrived. This is still 100% the truth and it isn't really relevant if you had seen it on pinterest as an idea to try to thaw some frozen food for you before baking vs a feeder for the snake.
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