I got a quest from someone saying I wasn't a real mage and wanted to challenge me. I said it's your funeral and we fought. However midfight a dragon got involved and the guy died, but now the quest is stuck in my journal "kill challenger"

Is there a way I can resurrect/restart the quest? i just hate broken journal entries.

I think you cab use the "setstage" command, however, I don't know what the reference ID for that mission is so i can't help you. Also, I think you could've just resurrected the mage as well using console command, and then kill him. it might work, who knows