I don't analyze oil, but I do analyze soil and rocks for a living. From what I've seen, UOAs show pretty much the same data as my company does, so I'd imagine we're using much the same instruments.
If so, then no, there's not really any way to know what compound a particular element came from. Let's take copper as an example. If I see 200 ppm copper, all I see is that number. I don't know if it came from some copper oxide or a copper sulphate salt or a copper nugget or if some joker threw in a multivitamin with copper in it.
However... it may be possible to narrow it down. In some cases, our clients ask us to add some chemical that will extract certain forms of copper and not others. Then when we run the sample, we can assume that any copper we see is only of that certain form.
For oil, I don't think the labs do any messing around with extracting anything, so what you see on your UOA is the total of each element in the entire oil. So you can't pin it down to any particular form of that element. It might be *possible*... if the lab knew a way to extract the compound you're looking for. That most likely depends on how many dollar bills you're willing to wave in their face.