In the UDT case, the set of outcomes is finite (well, or at least the set of equivalence classes of outcomes under the preference relation is finite) and the utility functions don't have any particular properties, so every possible preference relation the model can treat at all can be represented by a utility function!

(I should note that this is not UDT as such we're talking about here, but one particular formal way of implementing some of the ideas of UDT.)