Crankyweatherguy should NEVER be used for anything hurricane related. He is absolutely awful. He is calling this a cat 2 and saying it is weakening while pressure is falling and the storm is continuing to improve outflow, symmetry, structure, etc. He said Michael wasn't even a hurricane at one point and said it probably was a high end 1 or low end 2 at landfall. He's an absolute joke when it comes to hurricanes... just saying.
Regarding the warming cloud tops, this is quite typical in the process of a strengthening major hurricane and during the daytime as well when the cloud tops warm slightly. This storm is still strengthening quite rapidly as evidenced by the clearing eye and continued pressure falls.