Both me and the other member of fireteam just spent over an hour in the Vexcaliber mission first two encounters, both *only* using Dawning weapons (less than 10 ability kills each) and each got well over 1,000 kills, after having gone into that grind session with over 1,000 kills.
The Event Challenge is saying it is 2000 kills; the math ain't math-ing and I am frustrated....once I figure out how, I'll post screenshots of our Avalon session with weapon-specific callouts of kill counts, our current percentage of completion, and the number of kills out of 2000 that Braytech is saying that we both have.
If there are restrictions on the types of activities or types of kills or something for a challenge, that information should be available *somewhere*. BC the Melee kills from the glaive are not counting either, only the projectiles.