Suggestions anyone ?
If it hasn't fallen apart as yet, damage it in some way.
Next time you see this person act really devastated (even pretend to cry ) and show them the damaged key holder.
Ask the person what Louis Vuitton boutique they purchased it from as you want to return it and get it swapped or repaired.
Sit back and enjoy the reaction.
With a bit of luck, they will offer to get it repaired for you and bring you back a real one. If they bring back another fake just start the process over again.
That should teach them to never buy another fake!!