I need help making the Respawn Anchor (from 1.16 snapshot) system in 1.12.2

Hello,
I use MCreator 2020.2 for Minecraft 1.12.2 and I'm trying to add to my mod the Respawn Anchor from the 1.16 snapshots.
The only problem is that I just can't do it. Everything works fine util I move the player back to the Nether and I check the closest Respawn Anchor to check if it belongs to the player.
Here is the link of the 2 procedures I use :
respawn_anchor_on_right_click.ptpl
when_player_respawns.ptpl

Thanks for anyone who can help!