If you're going for a Silent Assassin rating, in the same mission "A Vintage Year" you can also kill by "accident" Don Fernando Delgado (he is located in the last floor of the hacienda, you will need a VIP guard suit to access this floor).
When he stops playing music, he goes in the larger central room near his own bedroom and stands on the balcony for a moment.
You just have to push him over the rail.
Note that the guard in this same room is sleeping.