Bloomberg currently has two great loves:
1. A desire to be in the White House
2. A long term love of money.
The way I see it, the main thing that could placate him from his White House dream would be the promise of massive tons of cash. The promise of something like an ambassadorship that would be worth its weight in million-dollar treasury bonds might be enough to persuade him. 
Our best hope is if lots of Bloomberg fans switch away from Bloomberg on Tuesday (preferably to Warren or Klobuchar in their home states, to Biden everywhere else). If Bloomberg underperforms after spending all of that money, he may realize that a Biden in the White House that he put there is worth more than spending hundreds of millions not to get there himself. If Bloomberg puts Biden in the White House, Biden will owe him big time. If Bloomberg cannot figure out a way to monetize that, he won't really be trying.
Rich people and corporations will be lining Trump's pockets hoping that he can win and then offer deficit exploding tax cuts in return. Fear of a "wealth tax" and other such taxes on the rich will make money flow like rivers for Trump. If the trade-off to that is some company Bloomberg owns getting a fat government contract to build roads or schools, I can certainly live with that. Someone's company has to do the work. If that company happens to be largely owned by the guy who helped us kick Donald Trump out of office, more power to him. Some of the money that Bloomberg makes can help fund Biden's reelection in 4 years.
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