I agree, you will probably never get an ID other than that it is an oncidium alliance. It reminds me somewhat in plant size and leaf size of my Cambria Bob Cat, but the skirts on the flowers remind me more of my Miltonidium Bartley Schwartz. I would say it's likely to be an intergeneric hybrid (as both of those are) but knowing the parentage will only ever be guess work.
Don't worry about that though. Lots of us grow NoID's. Just care for it as a general oncidium alliance plant and enjoy those beautiful flowers