I would like to join this RP too. I do like the sound of Light's idea more, but I do see the problem with the other characters involved being synced up properly. My suggestion is that perhaps the character involved in the killing of whoever has the dead end could get a pm with a small hint of what the victim's diary said, but not exactly what it said.

For example, let's go back to "You die on the 5th floor of a nearby apartment building". Now the GM would also PM the player he believes is most capable of actually fulfilling this entry and giving them a hint along the lines of "You'll find (victim) somewhere near this apartment building" and then leave it up to that player to try fulfilling that entry as best they can without knowing exactly how to do it, that way they must figure it out and that gives the victim the chance to try changing their future and avoiding the dead end altogether.

Also, just as a story element it may be possible that some players will purposely reveal their dead-ends for whatever reason of their own accord.