If someone takes my permission to do my wajib/ nafal qurbani from his wealth, will I have any right to claim the meat of that animal?
Answer
If after taking your permission he purchased a qurbani animal and slaughtered it on your behalf then you will be entitled to claim the meat.
However if he took your permission in order to slaughter an animal which already belonged to him then you cannot claim the meat and the qurbani itself will be invalid.