As far as I know a sand dune moves constantly. I can't imagine tracks would last a day.
Looking at the tracks it looks more like they were made in mud and later covered by sand dunes?
In short the first tracks were made in dry sand, eroded a little, moistened by fog, dew, or light rain, and then covered by dry sand again. The second tracks were made through the dry sand into the moist layer which was then crusted over with calcite and covered. Only the toe markings from the second tracks were preserved.
[0] https://journals.plos.org/plosone/article?id=10.1371/journal...
See caliche and Llano Estecado as examples.
Basically anything that covers the fresh print with a layer that is different enough chemically or physically that will then cause the layers to develop/preserve a boundary that can then break clean off millions of years later after everything is pressed/mineralized/whatever other processes happened.