Is it permissible for one friend to solemnize the marriage of his friend with a marriage contract paper, with two friends as witnesses, in the absence of a mosque or an Imam in the city?

The woman's guardian (wali) who gives her in marriage is, in order: her father, then her paternal grandfather, then her son, then her full brother, then her half-brother (from the father's side), then their sons, then her paternal uncles. If these are unavailable or are not qualified for guardianship (such as being non-Muslims), then the Muslim judge is the one who gives her in marriage; based on the Prophet's (peace and blessings be upon him) saying: "The ruler is the guardian of one who has no guardian." In the absence of Sharia (definition) courts, Islamic centers act in their stead.