In a qualified sense infinite certainty is possible about a finite thing. For instance, someone might have absolute certainty with no room for doubt whatsoever that something exists. They may have many uncertainties about their perception of what things exist and how and why. But they may have unshakable certainty that something exists, with complete certainty about this perception. I think this would qualify for infinite certainty about a finite thing. However, humanly speaking, it is impossible to be completely certain about everything.
Conversely, infinite uncertainty does not seem possible - about a finite thing - because one cannot be both completely uncertain that a thing exists and completely uncertain as to whether one's perception is mistaken, as this is contradictory.