Here are some of your problem for now until you give more details, in a glass cage you want both hides to be identical and snug so the animal does not chose security over thermo-regulation potential issue.
Your temps on the cool side should fluctuate 2 degrees at the most not 8, that is another potential reason for the animal not to eat.
Now for the other questions.
Please post a picture of snake by dollar bill for comparison or in your hand.
Where do you take your reading and what is your temp on the warm side?
How many attemtps total did you make and how many days apart?
DO NOT FEED unless you have answer all question and addressed all problem that have been pointed out so far, and giving it a least a week before offering again from adjusting issues.