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The short answer is “it depends”. First of all, it depends on whether the use case in question is a “user goal”-level use case (to use Alistair Cockburn's terminology) or an internal system use case (“subfunction” level) for which the actors are internal system objects rather than external actors like users (actual people) or external systems, as they are for “user goal” level use cases. The former type are the more well-known type, and typically consist of a sequence of steps that a user performs and the system's response to those actions.
For internal use cases (which aren't actually written out as often but can be a useful concept in any case), since the actors correspond to runtime objects within the system, the answer would be: yes, the roles in the use case should correspond to those actors because internal use cases are all about how internal system objects interact with one another, so they naturally align with the Interaction and Role concepts in DCI.
TODO: Complete this answer with a description of the considerations for external (user goal level) use cases, mentioning that one should keep in mind the distinction between “user roles” and “object roles”.