I can't say I'm sure because I didn't experience it first hand. I also don't have experience developing anti-cheats, an am super confident in Vanguard (I've never experienced any blatant cheaters.) I also recognize you can't give out information on players, and I'll try to avoid asking about that.
But can't you say with confidence that this is exactly what cheat developers want? They aren't developing something that'll get caught immediately, and even with review from multiple people, how confident can you be in this decision? It's an arms race, and if this decision ends up being false, it's a win for the developers, they know something they made slipped through Vanguard.
Personally, it was the crosshair placement for me. When detecting a cheater, do you consider factors like this? Lots would argue that this level of 'gamesense' can't be linked to this level of aim, but again, I'm no anti-cheat dev, so I can't be sure. Like I said, I didn't watch this live, and I haven't watched much of this player outside of these clips.
No hate at all here. Honestly, I hope it this is an isolated incident of the community jumping on something incorrectly, and the witch hunting is embarrassing for those involved. Thanks for actually participating in these conversations, and keep up the good work on Vanguard.