You did get the chameleon analogy right but I have to repeat that Victor did change each time he came back.

His first eviction happened when Paulie backdoored him. Paul knew all about the plan. Yet, when he came back, Victor didn't seek revenge on Paulie and Paul but aligned with them instead.

When he made his nominations in week 7, he nominated Michelle and Zakiyah which was the Executives' plan, Not vengeful nominations on his part. When he made nominations in week 8 after the double boot, he then went after Paulie and Corey but Not because of revenge but rather because he had switched alliances and gone with the new majority against Paulie and Nicorey.

On his 3rd try, he was once again HoH in week 11. He nominated Natalie and James when Nicole and James were the ones that actually voted him out. Natalie, who, with Paul, had wanted Victor to stay, became his target because she was judge to be more dangerous than James. Directing the vote against Natalie was dumb but not vengeful.