@PugLove888 Unfortunately I can't see what the other sim had queue'd up because mine went right to the dueling field.
It seems like it's similar to when you ask a spellcaster to simply duel. They go somewhere nearby outside and do it there. It's like the other sim isn't going to the dueling field, just somewhere outside and waiting for me. My sim goes to the field, eventually times out, and then goes to wherever the first sim went and completes the action.
It always works, it's just if I TOLD them to do it at the dueling field, I'd rather they do it there.