So... Should I give him the amulet?
Well, think of it like this:
Either there's an actual Goddess of Luck, or there is not.
If there's a Goddess of Luck, either she actually cursed this person, or she did not.
If there's no Goddess of Luck, the downside of giving away the amulet is having no amulet, and the upside is maybe this guy lives, if he's real and not a straight hallucination. And it's not that great an amulet, so, hey, might as well give it to him, then try to talk the adept mage guy into making another lucky amulet.
If there IS a Goddess of Luck, but she didn't actually curse this guy, then she's not going to be angry about you helping him, so you might as well give it to him.
If there IS a Goddess of Luck, and she DID curse him, it's possible she'll be mad about you helping him and levy some sort of ironic punishment on you for it, which will be entertaining for the rest of us to read about, so you should go ahead and give it to him.
So, basically, yes, you should give him the amulet.