It looks like a variation of a basic play called "POWER". (A lot of high schools run that like 50% of the time. Crete probably has power playing in his head while taking dumps and masturbating.)
At first glance I thought it might be a combo block but I don't think so. The left guard is trying to get to the LB from the get go, but the right DE pushes the left OT inside squeezing the path of that guard and gobbles up two blockers. It's why no one else in the SEC uses 220 lb DEs and 240 lb DTs. (It's also why the part of the board that thinks our real DTs suck bc they don't make sacks are DUMB AS FVKK.)
No one really messed up, LSU just had a guy who gobbled up two blockers.
(If it were a combo block then the LT should have been the one to pull once the DE crashed inside and handed off the DE to the guard. Again, I don't think so but the angle isn't the best.)
The TE actually holds his block reasonably well in that.
The play should work on paper but in reality it's too many butts in too small of a space. I'd also say the pulling guard looked a little slow. (It is Bleich on second glance.)
As for cutting outside, that outside LB being blocked by the TE is in pretty good position to control the edge. He does a good job of extending his arms and keeping the TE off of him. He can move outside if he needs to and the ILBs will be strafing too if he does that. Obviously there is a safety (I think off the screen. That looks like the right CB following Cleveland. Obviously, man coverage and probably 1 high.)
As for why the RB follows the guard, it's pretty simple. If they don't run the play as designed, absent something like the contain backer slipping, then they get benched.
Some of you coaching gurus correct me if I'm wrong.