U CANT AVOID THE EMBASSY!
and yes ur DoB and Name and everything will be mentioned on the ikhraj kayed with ur husband where it will be mentioned ur married.
if u need to change ur name in lebanon it will take a year,if not more, coz ur over 18 its very hard and will coast u money.
u know ur a typical lebanese, u recive an advice that is easy coastless and fast,but u dont consider it and go for the wrong advice that will coast u money and lead u to no where.