We received your e-mail. If sending organization and supervising organization do not have it, we regret to say, there is no other ways we can think of for you to retrieve it. The company you were assign to might have it also, but it is a low possiblity.
The contact point of the supervising organization when you were in Japan is as below.
Friend Nippon
TEL: 03-5297-8411
E-mail: info@friendnippon.com