I have solved this issue. The problem was that Volo.Forms.Questions.IQuestionAppService was missing the inheritance to IApplicationService. Just modify line 8 to public interface IQuestionAppService : IApplicationService and that fixes the problem
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From what I discovered while attempting to debug this problem the UI is not connecting to the endpoint in Volo.Forms.Questions.QuestionsController. In a non-tiered solution this error is not happening.
EDIT: the issue seems to happen when injecting Volo.Forms.Questions.QuestionAppService