This is a bug that has always existed on console. I submitted a ticket for it long ago with a YouTube video.
I’ll edit with the video clips later.
The same bug plagues the Reaver troop as well.
Here is what is happening: when the ability is cast, if the damage would kill the first target, the second set of damage skips the next troop and applies it to the one after.
So, if the damage is supposed to apply to troop N and N+1 but will be lethal for troop N, the damage is applied to troop N and N+2 instead. If the damage is not lethal for troop N, the damage is applied as expected to N and N+1.
Another issue with this bug is if there is not an N+2 troop to apply damage to (in the lethal N case), damage is only applied to N.
EDIT: @Nex Here are four examples of the bug from early December. As far as I’ve seen, it still acts this way today.