Holy shit that's too much. Are you both particularly wealthy or upper class or something?
This is a new friend, and it's their sister not the friend in question. Also, college freshman are expected to not have much money to throw around.
Flowers, unfortunately, could be seen as a romance thing. Most Americans aren't super familiar with meanings of specific flowers.
Absolute most I'd do is $50, the card with the handwritten note, and maybe the chocolate.
I'm astounded you'd think anyone would be dumb enough to believe that. This is just sad.