I have to agree with this. That was my take during the live game. Couldn't sleep tonight and watched the game again. Imo, 5 of their tries came directly from his bad defensive decisions.
The try at 12 minutes in, Douhi is jogging behind Frizell who takes the pass and crashes over the line. If he sprints to keep up, he could have taken Frizell down as soon as he catches the ball.
In the try in the 20th minute, he's way out of the line but not putting pressure on anyone because the attacking line is so deep. Since he's so far out of the line, it drags Alaimalo up and makes for an easy heads up play to kick over the top to the wing.
The try in the 30th minute is another bad read. He jams in again, this time it looks like he's covering Frizell, but he basically pushes across in front of Galvin who already has Frizel covered. That creates an overlap and there's not much Alaimalo can do.
The try on half time, he slides in after Galvin comes out of the line but appears to only have eyes for Gagai. It's as if he's taken by surprise that Ponga catches the ball behind Gagai. In any other game, Ponga knocks on at that point, but Douhi should have been ready to cover the player out the back. Special shout out here to Seyfarth as he's the only player in the defensive line who comes across to attempt to cover the play and doesn't give up.
The try in the 55th minute looks like Douhi only has eyes for Frizell and doesn't see how deep the attackers are standing or that Ponga is lurking around the back. Galvin has Frizell covered again and Douhi is left in no man's land and its 3 on 1 for Alaimalo. To top it off, Douhi stops in the line and has no urgency to get back.
Part of my issue is that Benji should have taken him aside at half time and told him to slide rather than jam in. Since he kept doing it in the second half, I can only assume that either Benji said nothing to him, ir he ignored the direction.
Sorry for the long post. Had to get it off my chest.