When is the Waw vowelled and when is it not vowelled in the word "tawallaw" in the two Noble Verses?

The waw and ya after a homogeneous vowel are letters of prolongation (harfa madd), and the sukoon does not appear on them, such as in "tawallaw" (تولوا) and "yu'ti" (يؤتي). However, if one of them occurs after a fatḥah, then the sukoon appears on it, such as in "ihtadaw" (اهتدوا) and "ʿalaykum" (عليكم).