What must I do after I vowed, if I succeeded, to spend 200 EGP in the path of Allah (100 EGP for mosques and 100 EGP for sponsoring an orphan), then I spent the entire amount on mosques only? Am I obligated to pay 100 EGP for sponsoring orphans, or is what has been spent sufficient?

The fundamental principle is the obligation to fulfill a vow (nadhir) in the manner specified by the person who made it, and it is not permissible to deviate from it without necessity. Therefore, you must fulfill your vow by spending one of the two hundred (units of currency/amount) on sponsoring orphans, as you vowed. It is not permissible to spend it on mosque construction or other purposes. Consequently, your obligation is not discharged except by fulfilling your vow to the orphans as you promised them.