dest: “{{params['box'].t1}}”

box:
    t1: "Albany"
    t2: "Albuquerque"

params:
  box:
    t1: "Albany"
    t2: "Albuquerque"

vars:
  wanted_key: box
  params:
    box:
      t1: Albany
    other:
      t1: Albuquerque