Looking at the replay, it was actually unlucky.
The knee injury caused him to fall back, lowering his head in relation to Smith's arm and creating enough space between the two guys for it to become a shot to the face.
If Crowder remains right behind him and doesn't hurt his knee, JR's arm probably hits him in his shoulder and it's a non starter.
Should he have done it? Absolutely not but it was a dumb decision made worse because he got hurt. If Crowder stays on his feet, JR may still get tossed but he's not facing a suspension.