Is the sufficient ghusl – where I make sure water covers my entire body, along with the intention – invalid if I perform a complete wudu' and then bathe without re-washing the wudu' parts?

Scholars have differed regarding the condition of uninterrupted sequence (al-muwalat) in washing the limbs for ablution (wudu').

The ablution accompanying the ritual bath (ghusl) for major impurity (janabah) differs from independent ablution. In the ablution for janabah, neither uninterrupted sequence nor order (tartib) is a condition, because one has entered into the major purification (ghusl), thus nullifying the ruling of the minor purification.

What has been narrated from the Prophet, peace and blessings be upon him, concerning delaying the washing of his feet until the end of the ghusl for janabah, may have been due to the uncleanliness of the place, or it may be considered commendable specifically for the ablution that is part of the ghusl. This is the opinion of the majority of scholars.