As stated before DarkUFO Rumors (unlike their spoilers) are unconfirmed so take these with a grain of salt.
I have some very valuable information. This is 100% accurate. Karl was not killed by Ben's people. Danielle doesn't die. In a future episode BEFORE the finale, We will see Charles Widmore on the island. The people who shot at danielle and Karl are in fact mercenaries hired by Widmore. So widmore has more than 1 team working for him. The mercenaries are totally decked out in camoflauge. They are their to retrieve Ben and kill everyone else. In the Ben Centric episode we see the mercenaries burning down the barracks. I don't know if they retrieve Ben. As of this moment one lostie dies in the retrievel, but this of course is scheduled to change.