@ jenn mangis,
There doesn’t seem to be anything wrong with either the key cap or the retainer. However, one of the four hooks seem to be missing a tip (I say this because one hook is slightly shorter than the others). Does this mean that I will need to have my entire laptop keyboard replaced?
Most likely the key doesn’t stay in places BECAUSE this missing tip.
Is it a metal part on the keyboard? If yes, you’ll have to replace the entire keyboard.
Don’t worry, keyboards are cheap these days.
If you give the the laptop model number, there is chance I can point you to the keyboard replacement instructions or service manual.
when I came home I noticed there was some ink under the key retainer–it looks like he was working with a pen to fasten the key back onto my keyboard–is this common practice?
No, it’s not common practice. 
