I think he did make it clear. He left notes all over the place - the contents of which have not been revealed. The tarot cards, for example, supposedly contained more than the fragmentary messages revealed to the press, but even those fragments contained enough information so that any police agency would have realized they were dealing with Black Muslim Five Percenters. They used certain stock phrases used by this group, for example.
Actually, I think the money demand - which seems to have come later - only arose because it seemed to be the only way that Muhammed could get them to take him seriously and assemble "enough" clues to be unable to deny the evidence. Remember, Moose and the others seem to have wanted this person, from the very start, to be neither black nor Muslim, and I think this was crucial in slowing down the apprehension of the pair. If their whole purpose was publicity, it must have been pretty frustrating! If it weren't such a deadly serious thing that had destroyed so many lives, it would almost be comical.
And of course, if it weren't such a serious thing with regards to the future. I still wonder about the "duck in the noose" remark -
As many Freepers have pointed out, "Like A Duck In a Noose" spells L,A,D,I,N = Ladin = Bin Ladin...