Is the marriage contract considered valid if the witnesses are not specified therein, and the deferred dower is not mentioned, and is the wife permissible for the husband before the dower is paid?

A valid marriage has conditions, the most important of which are the guardian (wali) and witnesses. It is not a condition to name the witnesses; rather, anyone present at the marriage ceremony who is eligible to bear witness is considered a witness, and it is not a condition to intend for them to be witnesses. The mahr (dowry) is not a condition for the validity of the marriage. It is permissible to postpone all or part of it for a known term; however, if it is for an unknown term, it is not valid. The wife is entitled to the immediate mahr forthwith, and the postponed mahr upon the arrival of its term or upon separation. A woman has the right to refuse her husband until he hands over the immediate mahr to her, unless she agrees otherwise.