So as I got GTA IV: The Complete Edition on Saturday I decided to try and get 100%. But then I found that I might have made a mistake. I killed Francis McReary rather than Derrick. Now the general stats say that I've only completed 83% or something of Francis' missions, and I figured I probably won't be doing another mission for him now that he's six feet under. Will it actually be possible for me to get 100% completion???

P.S I let Darko live. What does that effect???