Absolutely. Whilst Finkel Einhorn, At Your Service can only be completed in your turn, you can complete it at any point. Additionally, Fel Fire only deals damage when its trigger resolves, the damage does not tie in beforehand. Thus, if you have additional modifiers to the damage upon its resolution, they will take effect.

Level 0 Judge (Because apparently under 16 year olds can't get Judge certificates =/)
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