How about you don’t use copyrighted material?
Is it that hard to not use material, that you didn’t create or have no permissions to use?
Unless they play in 1.13 and above.
I believe the spot I have shown is much safer, because the player is not only stuck there, they also can’t hit or throw/shoot anything.
The portal is there with an invisible armour stand, which also has a hitbox, the hitbox is as big as a player, so aim at a corner or bottom edge to do damage.
The most they can do is AoE damage.