All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
The majority of scholars hold that it is impermissible for a virgin or a previously-married woman to conclude the marriage contract for herself or for others and that her statement in marriage does not count. Hence, if the two women were the ones who concluded the marriage contract on behalf of the guardian or by his authorization, then, this marriage would be invalid according to the majority of scholars.
If the guardian concluded the contract and pronounced the wording of the guardian and the women’s role was confined to registering the contract (the marriage official), then the marriage would be valid.
Allaah Knows best.