Thanks for the idea. Unfortunately, I can not get that to work. For some reason Cases is not penetrating the TagBoxes and the like that occur when you use ToBoxes. The code below, for example, returns an empty list even though if you actually look at the "ToBoxes" expression the "Meta" stuff is there with exactly what I want.

Cases[ToBoxes[Dataset[{{4}},Background->Blue]],HoldPattern["Meta"->_],DirectedInfinity[1]]

Further help would still be useful to me. Really, there should be something in at least the Dataset` context to get this stuff out, but I am hopeful that someone is savvy enough to figure out a good way of getting the formatting out.