Question

Carlos, a Philippine citizen, owns a piece of land in the Philippines. He subsequently passed away and his estate is now subject to probate proceedings in the Philippines. However, there is a dispute regarding the validity of his will, as some heirs contest its authenticity. As part of the probate proceedings, the court needs to determine which law governs the formalities for the execution of the will.

Discuss the applicable principles of choice of law, specifically focusing on the Doctrine of Renvoi and Doctrine of Processual Presumption, in determining the governing law for the formalities of the execution of the will under the lex rei sitae principle.