No, Iluminado Iway was certainly not a hoax.  I corresponded with him
off and on for about 15 years.  I sent him some clothing, and some
tools so that he and his sons could work on boat engines.  In return,
he sent me quite a few boxes of shells - mostly common things, not
identified, not very well cleaned,  but whatever he and his family
could find around their native island of Culion.  Some of the
material was good quality, some not.  But,  as others have said, he
frequently wrote long letters expressing his gratitude for any help
given his family, and occasionally asking for assistance when their
needs were great.  I am sorry to hear of his death, and hope his
family will be able to carry on adequately without him.
Paul M.