[1.12] How to change dimensions without creating a portal

[VoxelBuster]

I created my own custom portal block that when the player collides with it, they are teleported to a (currently empty) dimension. The problem is that upon being teleported for the first time, a nether portal is created where the player spawns. I don't want to do this because I will be generating structures in that dimension later. How can I move dimensions, preferably to a specific position within said dimension, without creating a new portal?

 

Current code:

@Override
public void onEntityCollidedWithBlock(World worldIn, BlockPos pos, IBlockState state, Entity entityIn) {
    if (entityIn instanceof EntityPlayer) {
        entityIn.changeDimension(WorldUtil.dim_outpost.getId());
    }
}

[VoxelBuster]

It appears that this is buggy behavior with when the world I was testing on crashed the game. Creating a new world seems to have resolved the problem.

[VoxelBuster]

Never mind, it seems to be doing it either way.