Not in the cards. Dem megadonors tied to Wall Street and hedge funds fiercely oppose Warren, while passing over the many Black VP choices would infuriate the Black segment of the Democratic base. My guess is that Biden will pick Harris.
The Dem megadonors don't want another Obamanation, which is what they'd get if Biden actually got elected and sworn in. He'd be removed for inability to carry out his duties, or just "die of natural causes" before May 2021 rolls around.