The WARN Act doesn't mandate severance payments AFAIK.
I think perhaps that's why poster used "for this situation" -- if a company doesn't want to have to provide advance notice, their only option with WARN is to do it with this kind of severance payment. Not sure if it was intended but that's a pretty cool outcome of the law.
16 x 7 = 112 days, I’m not sure I understand your comment? Even if it was business days only, 5 x 16 = 80 which is still above the minimum needed.