Rather than nerfing the Evasive abilities, why not leave the ability in the hands of the players?
Below pictured is a choice a player will have to make when playing and playing against an evasive dino.
Right before the hit animation, both players must choose a direction and each player has 5 seconds or RNG will decide.
For the Indoraptor, the player has to choose to dodge right or dodge left.
For the other player, they have to choose to chomp left or chomp right.
If the chomper hits the same direction as the evader, the chomper hits.
If the chomper hits the opposite direction, it misses.
For back bitters, right before the back bite, both players have to choose a direction again and the back bitter has to choose the same direction as the evader to hit the evading creature.
This choice only comes up when an evasive move has been chosen.
Where side-step is a 66% chance, both players hit 2 of 3 directions, left, right or down as in ducking. The attacker will need to hit the same 2 directions as the evader to hit them.
This will take the RNG out of the game and put it in the hands of the players.