Whoops, thanks for catching that - I will fix that in the next edition of the PDF. It is intended to be discarded on a failure.
Or, if your players don't like that rule, feel to let it go back into their hand. It doesn't change the balance too much, and I subscribe to the player first philosophy in whatever makes the game more fun for the group. :)
Finally, thanks so much for checking out the game! Would love to get any other feedback you have in the future.