Dear Cursed:
A single one of those problems might indicate an incompetent employee. At the point where your subordinate's list of follies includes "failed to murder an incarnate of Immonhiel", I think you need to step back and realize that, in fact, very few subordinates are competent to reliably murder incarnates of Immonhiel. Whatever position you assigned this person to sounds so heavily cursed that I don't even know, without further examination, whether Aspexia Rugatonn would've done any better.
Obviously I'm not saying that you shouldn't torture him for his failure, but it sounds like you have a project drama problem that goes far beyond the competence of this particular subordinate.
Unless he is regularly in the habit of hiring gnomes and failing to execute empyreal incarnates on projects previously lacking drama, in which case I recommend execution.