Is a marriage contracted in the Sharia Court in Syria via an official power of attorney considered valid and legitimate, and does it not necessitate a new contract with a marriage officiant upon the wife's arrival in the Kingdom, especially since the husband cannot travel to Syria?

If the marriage contract is concluded with an offer from the woman's guardian and an acceptance from the man's representative, in the presence of witnesses, then the woman becomes legally married to the man, and there is no issue with the validity of the marriage. As for the legal documentation of the marriage, that is a matter to be inquired about from legal specialists.