What do you understand first by moral obligation. For me it means doing something you do not have to do. Because it a good thing to do.Nobody will hold them legally. But morally they are as bankrupt as wanjigi.
What I understand here is simple. Here is rich developed country whose systems [anglo leasing didn't have addresses in karatina and the money was wired outside the country] are being used to fleece a poor third world country. Swiss and Brits have moral obligation to nap Wanjigi and his friends who opened phoney companies under their jurisdiction,using phoney addresses in the same places, bank accounts, and got money wired directly.
At worse they can arrest them for money laundering. That remain the only hope against some of our powerful characters. If Wanjigi assets are seized..abroad...there is some chance..we will get something back.
Of course we know what Brits and Swiss do..turn a blind eye...as they set them phoney islands like cayman to fleece poor countries.
On what basis do you say that they have a moral obligation?