I dunno, at least for me I'm not totally convinced it's a pirate of a pirate we've got here, but I can't completely dismiss the possibility. I don't think there's any way to know 100%, especially since the game did have a form of protection, however small and fast it was cracked. The important thing is it's dumped so meh.
I was taking a look in VRAM and noticed that there's more text that's unused in the intro. The story cuts off at "comes out to fight with Prince of Darkness for justice to rescue" with no period or anything after "rescue." Here's what's in VRAM.
It possibly was meant to say "rescue his disappeared friends.." There's also the text "A journey," who knows what that line was supposed to be.
Edit: On second it looks like the text would have been "A journey in Imaginable Island begins.."