English to Spanish Other Law (general) Power of Attorney of legal custodianship

I am translating a power of attorney of legal custodianship executed in Cambodia that a father is granting to the biological mother of their daughter in question. The daughter is of full age but has some kind of disability.
The term release appears in 2 sentences:
1. "My attorney-in-fact shall have full powers..to do all acts on my behalf that I could personally do, including but not limited to release the legal guardian of my daughter."
2. "I do hereby voluntarily release in full the legal custodianship of my daughter".

I have doubts as to the term "release", because of the relevance it has, and although it may seem straightforward I need some confirmation, please.
According to the dictionary, release may mean: relinguishment of a right (renuncia) and in general, to make available to the public (dar a conocer). So, in the first sentence, would you say it means, ¿dar a conocer el tutor legal de mi hija? (i say this because on a different document I am translating of the same person, it hightlights the confidential nature of her disability).

In the second sentence, it makes more sense for me to translate it as "renuncio a la guarda legal de mi hija".

Thank you for your views.