Im the player who got stuck like that,
1. To explain it better, i made a mechanical user (extra utilities) shoot a matter cannon (AE2) into the sky (i was on the surface), it shot several times perfectly fine, I then jumped on top of the block, it shot, i took damage, and the server closed (didn't crash), upon starting the server back up, I was stuck inside of a stone block and shortly suffocated (kicking was happening while this was happening)
Now, for your suggestions
1. I'm dead, and I get kicked before I have a chance to respawn, so I can't be teleported
2. I believe that wouldn't help, as I'm already dead, I'm unable to respawn
3. Again, I cant respawn