Hazel refers to himself here as Elisha's servant. Hazel uses this rhetorical question to emphasize that he does not think he could do the terrible things that Elisha has said. This can be written as a statement. AT: "I could never do such great things!" or "Who am I, that I would have the power to do such things?" (See: [[rc://en/ta/man/translate/figs-rquestion]])
Hazael is talking about himself. He speaks of his low status and lack of influence by comparing himself to a dog. Here a dog represents a lowly animal. AT: "I am as powerless as a dog" or "I am as powerless as a lowly animal" (See: [[rc://en/ta/man/translate/figs-metaphor]])