There aren't even 900 hours in a month. That's 765k for 900 billed hours, and you have to imagine that a good chunk of unbilled hours also occurred. So maybe that's for the equivalent of 8 months of boring work. Not continuous 8 months either, you have to schedule other things between prepping. A lot of money. But not for a billion dollar lawsuit.
As for "who can afford this" is a company worth tens of billions suing over a major product line vs a trillion dollar company.
Once they get the contract. I guarantee that the recruitment process and negotiation process was more involved than a phone call. And there could be work specifically excluded as "billable hours" that is still work. For instance, is the time to fly out compensated?
All work that an expert does for a case is billable, including travel time. However, experts will frequently provide discounted or even unbilled work for individuals in certain circumstances (like criminal cases where the expert is testing in a forensic capacity to counter improper forensic analysis presented by a prosecution expert).
Some experts charge for their time at a reduced rate (e.g. 50%) for travel, some a predetermined amount (taking the risk of delays on themselves), some only for the cost of the tickets, hotels, meals, etc.
There is, AFAIK and based on what I can Google, no universal answer.
It could easily be more than 9 hours. How many people spend longer than that interviewing for a technical position across five rounds? And this is for one of the few experts Samsung will put up to defend a $xxx million suit.
Plus, he works for MIT. He probably needs to clear his consulting work, which could be quick or not. MIT might have wanted a percentage. And if he wanted to use a grad student to assist him in prep work, negotiating that can add up too.
There are other ways to add to the precontract numbers, but that should be enough.
As for "who can afford this" is a company worth tens of billions suing over a major product line vs a trillion dollar company.