Look again at the chart you posted.

See how on the second day, the temperatures of different parts of the rover peak at different times of day (e.g. the right front wheel RFW peaks 3 or 4 hours ahead of the LFW).

This will (probably) be due to the orientation of the pathfinder rover on that day and having shadow on the left in the morning and the right in the afternoon.

If you are going to make proper use of stuff like this you also need to record what rover activity was on that day, whether it was moving or stationary, what nearby rocks might have shaded or reflected sunlight, which way the rover faced, whether it was advancing over ground in shadow or in sunlight....

And then you need to calculate the thermal response of rover and surface materials to sunlight and the ambient conditions, and look at hystereisis of phase change in potential volatiles.

In short, it is a VERY complex issue and you can't prove the point with a single graph grabbed off the 'net. You don't even know what it is measuring, let alone what it "proves".

So, if you're prepared to do some serious work, I'll listen to your conclusions, but if you just keep parroting stuff, I'll put a cloth over your cage.