And think about how close Trump was to pulling this off as apparently Ukraine had basically agreed to launch the investigation just before the WB report came out.
Had they done that, Trump would have had what he was looking for. Ukraine would have announced and Investigation and asked Bill Barr to cooperate. Barr would have his deniability saying "I was asked but had nothing to do with the genesis of this (thus Rudy)' And Trump would use investigation, regardless of eventual outcome to the same effect the announced investigation on Hillary harmed her run. Ultimately it would be gravy to Trump if they could manufacture dirt to actually see Biden be guilty but the damage to his election chances is his paramount goal.
And even if the WB or any of this stuff came out after the Investigation was launched and announced it would simply look like Dem's doing damage control and trying to distract. That is why Rudy raced onto Cuomo Show to try and get it out prior to the WB announcement they knew was about to be broken wide open. There was a wide eyed desperation in Rudy to get that narrative set first.