Am I assuming you're trying to claim the Jonin Medal Rewards with a trial medal?
Considering it's not an actually bought medal, you do not receive the additional benefits it comes with.
Kyuubi Naruto is restricted only to those who buy the Medal itself.
Trial Medals provide only the benefits outside of the "claimable" rewards.

It's not.

As I've explained prior. Kyuubi Naruto is restricted for players whom bought the medal.