Apple will replace the whole keyboard. The only solution you could do at your own is to buy an official scissor (the keyboard part that ties the key), but don't buy a "1" key since it won't do anything (I fell in that mistake, and nothing fixed)
Can't tell from the pictures, but if the mechanism isn't physically broken it might just have been badly placed i.e. not really snapped in place. I've seen tutorials for cleaning the keyboard where they show detailed instructions on how to put individual key mechanisms back in place. Of course, if that fixes your problem I dare say the "genius" didn't look very closely.