The people responsible are probably all dead by now, given that the crimes occurred 73 years ago. The people were acting on orders of their government, so the only recourse now would be payment to the families of the victims. The payments seem to be exceptionally small to me.

Using an analogy: Do you think governments should help subsets of their population that are affected by sudden extremely rare disasters? Part of the goal of a government is to provide public goods - like fire fighting services, for example. Maybe your argument is "they should have been insured against having their family members killed by the state"? Pretty clear to me (at least) that this is an absurd position to hold.

Of course, the fact that this "disaster" was directly caused by the government probably builds a stronger case for the government having to use some of its budget to help them out. That just seems like a good policy in terms of incentive design.

Edit: Maybe your argument is that Indonesia should have (in effect) sued the Netherlands if they wanted to get compensation for their citizens?

Those responsible were soldiers acting for the state. The state still exists.