Do you have any sources on this other than the article linked? I couldn’t find anything on this doing a cursory google search in french. It is widely known he wrote it in a short amount of time due to his work on “Le dernier jour d’un condamné” and “Les orientales”. I just think it’s a great bit of trivia on Hugo, but would hate to disseminate something that I have found no real evidence of. I’ll keep looking though! I think I will hit my library for a good bio on Hugo in French.