As usual, Cory comes to the rescue. But just to insure that ALL files associated with MacKeeper have been removed, you could do a search by entering the term MacKeeper, and then select your entire internal drive to be searched. Myself when I want o remove an application and its associated "pieces", I use the excellent freeware program AppCleaner, available from here:
https://freemacsoft.net/appcleaner/
It works quite well, but it does not catch every file associated with the application. So, after using AppCleaner and removing all the stuff, I launch another excellent freeware program EasyFind, enter the application name, and in most instances it finds some more files associated with the application already removed.
Hopefully you did get everything for MacKeeper.