Switch to aspen bedding. I had the same problem a week an a half ago. Seething was the same, 94 tstat for the heat lost through the tub. 80 degree paper towel. The aspen allows you to set tstat at like 93 and get a 91 degree hotspot. Surface temps of aspen will be like 80 but the snake will just push the aspen around so they can get to the 90 degrees. only downside is it takes an extra minute to clean. Switch to aspen.
Also what temp gun are you using? I have a 412 and it is usually spot on with my accurite and herpstat maybe -1/+1 at times.
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