I'll be Tim Kaine and that would mean it is over for Trump.
If this is true, it would be a Eagleton '72 moment. There would be no recovering from this. You could nominate the best candidate in the world and they would still lose. It would be disastrous and would put great doubt over the Democratic party's judgement.
No, it wouldn't be like the Eagleton thing. I don't see anything about anyone suffering from bouts of depression. It's also not 1972 anymore and Donald Trump is certainly not the caliber of candidate that Richard Nixon was back then.