Are "invalid marriage" (az-zawāj al-bāṭil) and "corrupt marriage" (az-zawāj al-fāsid) synonymous terms or different?

A corrupt marriage (نكاح فاسد) is one about whose invalidity scholars have differed, such as a marriage without a guardian (wali). In contrast, a void marriage (نكاح باطل) is one whose invalidity scholars have unanimously agreed upon, such as marrying a milk-sister. The implication of this distinction is that a corrupt marriage necessitates annulment (faskh (definition)) or divorce (talaq (definition)), whereas a void marriage results in separation without the need for annulment or divorce. Furthermore, the waiting period (iddah (definition)) is obligatory in a corrupt marriage, but not in a void marriage whose invalidity is unanimously agreed upon.