You'll be waiting forever. Malignant narcissists never admit to having made mistakes, never admit to having been duped, etc., even where they actually have a plausible basis for arguing that their failure could legitimately be attributed to others.
"Operation Warp Speed," and all of the fall-out from it, was the single biggest policy blunder of Trump's presidency. It's his biggest weakness, politically, on his right flank. This recent gambit, promising to "investigate" the pharma companies with respect to other health-related issues, is rather obviously the bright idea of somebody currently in Trump's camp, advanced in the hope of providing Trump some political cover.
Bobby, Jr.'s emergence in recent days was likely the catalyst.
Have any of the R candidates denounced the Frankenshot?