The second witness was not present when the marriage contract was done; is his marriage valid?

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Check below answers in case you are looking for other related questions:
What is the ruling if the two witnesses did not hear the woman giving her consent to the marriage?
Getting married in the embassy with two non-Muslim witnesses

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Related Answers:
She does not have any wali (guardian) for the purpose of marriage; can the director of the Islamic centre or her maternal uncle give her in marriage?
Marrying without officially registering the marriage
Do the bride and groom have to be present at the wedding party (waleemah)?
What is the ruling if the two witnesses did not hear the woman giving her consent to the marriage?
Getting married in the embassy with two non-Muslim witnesses

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