My cheesecake formula is 3# cream cheese, 7 eggs, 13.75 oz sugar, .25 oz cornstarch, 1TBL vanilla, 1 TBL lemon juice. Mix as usual (cream cheese, then sugar/cornstarch, then eggs, vanilla, juice). It bakes up firm enough to use under fondant; when I do it for restaurants in individual servings, I top it with a sweetened sour cream.
Rose used fondant for that bar mitzvah cheesecake (where she says “Plumes, I suppose.” That line still cracks me up all these years later!!) and it was fine (keep in mind that this was her fondant). Good luck! Do a trial run and let us live vicariously!