Grounds for defamation?

I was seeing some controversy regarding a self proclaimed comedian who used Ms. Rachel’s likeness to touch on some distasteful topics that would certainly hurt her brand if someone mistook her as Ms. Rachel. I know comedians tend to do this all the time with random billionaires or actors, but for this case I personally see it being more catastrophic to the brand she’s built. According to media she’s attempting to sue this woman but is that truly possible? To what extent can you get away with using someone likeness? Google says she’s based in NYC. I’ll attach one example below. https://www.instagram.com/reel/DZ2hJ8-RDi3/?igsh=dHFoM3oyZ3ZrNnZp