Nope, it's not bug. It is working well.
Blue Mt. Elite chooses unit, not row. In that situation, Werewolf can't be targeted. You need to target a unit to damage it.
But can be better with choosing row over a unit. Interaction will be the same, but could kill immune units immediatly. Little bit boost.
Can't choose row by itself, because think like this, there is a 2 unit on the board, one of them is on Melee row, other one on Ranged. BME can target both of them.
Blue Mt. Elite chooses unit, not row. In that situation, Werewolf can't be targeted. You need to target a unit to damage it.
But can be better with choosing row over a unit. Interaction will be the same, but could kill immune units immediatly. Little bit boost.
Can't choose row by itself, because think like this, there is a 2 unit on the board, one of them is on Melee row, other one on Ranged. BME can target both of them.