Couple of comments...
1) There is a difference between "making himself available as a consultant" and having an actual paying consulting gig. The former could be a PC statement.
2) It wouldn't be unusual for someone in Lewis' position to have an agreed upon severance package before everything went down. I've seen packages administered/paid out over time instead of in lump, and the person was paid out over time and remained "under contract" - so they couldn't do any damage or risk the payout.
3) Often times there is a little give and take to a termination/severance in order to get a full sign off of a release for future claims. Even if you feel you're in good position as the company, it can be worth a smaller payment to make sure the problem goes away without incidence (just negotiated one of these myself for my company a couple months ago).