Visible crew/equipment: Very near the end, when they are doing a pan-out of the deserted building, there are three of the five characters standing in plain view. The other two are in the building, one is helping the other cope with a wound. When they do the pan-out, look through the bottom right "window hole." There is someone standing there, and it can't be any of the five people mentioned. (02:05:35)
Visible crew/equipment: In the shot where the rat is being lured into the cell by Dantes and the priest, right before the cup is pulled away and the trapdoor is shut you can see a crewman's booted feet for a brief moment. Presumably to keep the rat going in the right direction. (00:44:20)
Visible crew/equipment: While Edmond is Fighting Fernand in the dining room there is a crew member that is in one of the mirrors for a second.
Answer: I believe it's just because there is a dirty smelly man that she doesn't recognise visiting her ailing grandfather, she just wants to keep an eye on things.