Why bother? You'll give up your severance, you'll lose an expensive case, and you'll never work in the industry again. Look at the anti-poaching class action from a decade ago. The companies admitted they colluded to drive down salaries, lost the case, and the payouts to the plaintiffs were still pathetic. In this case, Intel has this so water-tight that they'll never be found guilty of anything. No payout. Just a lot of pain and wasted time and money.
Yes, the layoff sucks and is unfair. But it is not illegal. You gotta move on, for your own sanity. F*** Intel.