They're blatantly wrong because they're looking at Gane's actions. Ngannou drops his hip first for the scissor sweep before Gane even lifts his foot, so even if we were gonna to bullshit and say Gane went for the lock, it wouldn't matter, because Ngannou was sweeping him.
Secondly, don't know what angle they saw it, but if you're going for an ankle, you pinch your knees around his leg, but his knee was just going straight forward like he was piercing the guard to move forward. Either he was trying to pass, or going for an ankle lock poorly
Thirdly, Francis had an overhook on Gane's arm. Which means he wasn't going to be falling backwards if he tried. What he could try to do while overhooked was, again, trying to pass by piercing the guard, which is why everyone assumes that was the case, or he was going for an ankle lock stupidly.
Fourthly, his head never goes backwards. He stays on top with his head forward for this move that you need to fall backwards for, and yet, Gane's head only starts going backwards after Ngannou's foot comes up and he starts hipping Gane over.
I mean, it's as 101 of a sweep you can get.