Checking blocks in other dimensions

I'm making a Half-Life mod and I'm starting with a Displacer Cannon item that allows you to teleport to Xen( with the end as a teleport until I make the dimension). It's working well but it's common to teleport inside of blocks when you go to the other dimension. I can't find any way to check for blocks in the dimension the user is teleporting to though, so I can't find any way to prevent this without teleporting the user really high up. I tried doing an explosion but that seems to stay in the dimension the item was used in.

This is the procedure used when the item is right clicked: (oh also it seems like you can't directly upload images but i dont feel like looking for image hosting websites so im just gonna type it)

Event trigger - triggered by external call
or when (global trigger): No additional trigger

Play sound [displacercharge] at x: x y: y z: z level: 1 pitch: 1 category: player

Wait 20 ticks then on server-side
do
 if ID of dimension Event/target entity is in = End
 do
  Switch dimension of Target/event entity to Surface
 else
  Switch dimension of Target/event entity to End