Looking at it a couple of times, the center tries to take on Leonard Williams and gets obliterated, with Leo shoving him backwards in to the right guards left calf.
The right guard is on the ground because DHall is taking on the RT, and the RG kind of dives toward DHall's legs (which I believe is a penalty? Going low on somebody from behind who is already engaged), this in turn exposes the RG's lower legs to the flailing Center, who lands on them like a giant sack of lava rocks.
The RG ended up on the ground of his own accord, and his teammate fell on him after getting rag dolled by Big Cat. The Center was probably embarrassed and wanted to take it out on somebody. But he chose the wrong person.
This whole thing stinks of somebody whining to the Refs because it came about long after the game was over.
I looked up the penalties, and there's Clipping and Chop Block. The RG was close to doing a chop block, but he didn't commit a penalty.
Like said up above, the RG did roll up on DHall's ankle, causing him to stumble and trip over him.
The RG was injured by the Center that Leo tossed on top of him. Both were humiliated.
FYI:
In the NFL, blocking someone already engaged high by a teammate is often an illegal Chop Block, a 15-yard penalty, where one player hits low (thigh/below) while another engages high, illegal on passes/kicks and all runs now
An NFL clipping penalty is a 15-yard foul for blocking an opponent from behind, typically below the waist, and is considered a dangerous personal foul, though it's less common now as many similar plays fall under the broader "block in the back" rule (10 yards). It's illegal anywhere on the field if from behind and below the waist