fun fact, he actually went 4 weeks, which is when we gave up because I was convinced that was too long, but after giving him over 3 live meals we tried some more F/T and he had absolutely no interest, also we tried that method you mentioned as well, no luck. like I said, we'll try again sometime.
I don't know if it will work for you, but after thawing a rat I aim the hair dryer at the rat's head and point the dryer at the cage with the door cracked. My snake always sticks his head out of his hide and starts to S-pose, and that's when I offer the rat.