Does a woman who has recently embraced Islam sin if she bears witness in place of a man to the marriage of a non-Muslim woman?

We have not come across any statements from scholars regarding a Muslim woman testifying to the marriages of disbelievers and whether she incurs sin by doing so. However, it is well-known that a marriage contract is not validated by a woman's testimony, and for its validity, the testimony of two just Muslim men is required. It is preferable for both Muslim men and women to generally avoid gatherings of disbelievers, and to avoid testifying to their marriages, in order to avoid the differing opinion of those who consider the marriages of disbelievers to be invalid in principle.