Why would Twitter do that? They have sent their money by their own greedy decision. It is like asking for a compensation from a food manufacturer, when you dont like how restaurant prepared your meal. No one forced people to send money. When you see an ad on TV-shop saying "Buy this product, it has a discount only today!", do you immediately pick up a phone to make an order?
Where in the world, when the meal comes in a bad way, you can't get a refund or a compensation? If you find a strand of hair in your soup, you can ask for a refund (or at least a dessert). But yes, there will be no compensation, even though your comparison doesn't make too much sense.
If they can prove, that hackers got other account owners personal info (passwords) by twitters security breach, than they can at least hope on something. But I'm sure that twitter layers will win case in any scenario. No one forced people to send money.
Twitter already said that their investigation shows the 'hackers' got access to some Twitter's internal tools by social engineering their employees, so 100% their fault. If this happened with an exchange, and not with a social network, they could have been in more trouble (e.g, if people send money directly from their accounts, they would probably need to reverse them or compensate people that sent the money).