The ACTUAL code.

on right click:
  if clicked block is "<acacia_door>":
    execute console command "/teleport <player> @e[sort=nearest,tag=closet]"
    execute console command "/effect give <player> invisibility 1000000 1 true"
    execute console command "/tag <player> add inCloset"

if player tag is inCloset:
  if player crouches:
    execute console command "/teleport <player> @e[sort=nearest,tag=closet] ^ ^ ^1"
    execute console command "/effect clear <player> invisibility"
    execute console command "/tag <player> remove inCloset"