I don't think she'd help Trump pull in swing states. She is indeed Trump 2.0 and her protracted gubernatorial election battle in Arizona is probably turning off a lot of people.
Kari Lake Still Believes She'll Win Her Election Case (newsweek.com)
4/25/23
"Former Republican candidate for governor
Kari Lake is not giving up on her hopes that she can still reverse the outcome of last November's race in Arizona.
On Tuesday, Lake provided an update on her election lawsuit to her supporters, saying that her team is waiting on a judge to make a final ruling and that she's prepared to take the case to the
Supreme Court if necessary."
He knows his worshippers won't leave him if he doesn't do debates. And at the same time, going up against DeSantis in a debate could hurt him with people who like to hear reasonable, well-articulated plans and points of view.