Auto-death and shields on death mechanic.

[Medvezhak]

I wonder why if person 1 and person 3 die, person in the middle gains 0 shields. But if person 1 and 2 die, person 3 gains 6 shields. How does it work? Why this order is critical to work? Are there any other pictos which might not work as intended due to positioning? Very frustrating...