So, Tre wasn't hurt enough for you? But, both instances had player (a) hit player (b) with an intent to cause severe bodily harm. Both instances happened outside the scope of the game. Player (b) was injured on both played. Both plays had player (a) land a blow from behind, which drove the head of player (b) into the ground/surface.
It is not harder to make Gronks hit seem worse when one points out that the hit happened while play had ceased. Gronk also used a brace as a weapon. AND, Tre was already on the ground when Gronk launched.
I suppose the only valid argument you have is the extent of the two injuries, as Tre only got a concussion and didn't have his neck fractured...
You are aware that criminal charges can, and should be brought, against Gronk, regardless of Tre ONLY having suffered a concussion.