A foreteller converts to Islam after seeing Jinn worship Allah?

Volume 5, Book 58, Number 206:
Narrated 'Abdullah bin 'Umar:

I never heard 'Umar saying about something that he thought it would be so-and-so, but he was quite right. Once, while 'Umar was sitting, a handsome man passed by him, 'Umar said, "If I am not wrong, this person is still on his religion of the pre-lslamic period of ignorance or he was their foreteller. Call the man to me." When the man was called to him, he told him of his thought. The man said, "I have never seen such a day on which a Muslim is faced with such an accusation." 'Umar said, "I am determined that you should tell me the truth." He said, "I was a foreteller in the pre-lslamic period of ignorance." Then 'Umar said, "Tell me the most astonishing thing your female Jinn has told you of." He said, "One-day while I was in the market, she came to me scared and said, 'Haven't you seen the Jinns and their despair and they were overthrown after their defeat (and prevented from listening to the news of the heaven) so that they (stopped going to the sky and) kept following camel-riders (i.e. 'Arabs)?" 'Umar said, "He is right." and added, "One day while I was near their idols, there came a man with a calf and slaughtered it as a sacrifice (for the idols). An (unseen) creature shouted at him, and I have never heard harsher than his voice. He was crying, 'O you bold evil-doer! A matter of success! An eloquent man is saying: None has the right to be worshipped except you (O Allah).' On that the people fled, but I said, 'I shall not go away till I know what is behind this.' Then the cry came again: 'O you bold evil-doer! A matter of success! An eloquent man is saying: None has the right to be worshipped except Allah.' I then went away and a few days later it was said, "A prophet has appeared."

This is one of the weirdest and most disturbing passages I have come across so far.

Foretellers = Fortunetellers = Fortune telling is a practice used by the occult, and is the art forecasting the future supposedly by supernatural means, is an ancient practice which is still popular today. Fortune telling is also known as divination. The one who practices this activity is known as a diviner. Fortune tellers include all those who claim to predict your future or advise your life through such means as ouija boards, mirror mantic such as crystal balls, mirrors, rock crystals, extra sensory perception (ESP), horoscopes, astrology or biorhythm, telepathy, palm-reading, etc.

Jinn = A race of fire created by allah - normally demonic of origin.

So, a foreteller, a member of the occult, sees demonic spirits advising an individual to convert to islam, and he does.

I really cant see anything wrong with this picture. Can you?