Lewis is still hurting that he never had Tyson's popularity, appeal with the casuals and where even though he has more legendary accomplishments in the sport, Tyson is the guy every one loves and talks about. He knows the more Tyson carries on with his legend league tour, the more Lewis goes back to being a historical footnote at best.
Lewis had 2-3 fights left with HBO going into the Vitali fight. He chose to renege on that deal and retire rather than risk losing