That is an interesting option, but I disagree.
I Don’t know if your from the UK but in American English “Deal x damage to the first enemy, and Silence them”. “Them” does not mean “Silence the next enemy that is below the one you just killed” in this case it would mean “the First enemy”
The “design” has a bug, hence my original post. I suppose they could change the wording of the ability if they “designed it that way”