If you have dormant code, as in running everywhere but not getting worked on anywhere, a "translate to shitty rust before ever touching again" has a certain appeal. Not the appeal of an obviously good idea: chances are the "shitty rust" created through translation would be so much worse to work on than C with some level of background noise of bugs (that would also be present in the "shitty rust" thanks to faithful translation). In C, people have an idea about how to deal with the problems. In "shitty rust", it's, well, shitty, because rust people are not used to that stuff.

But there's a non-zero chance that someone could develop a skillset for iteratively cleaning up into something tolerable.

And then there are non-goal things that could grow out of the project, e.g. some form of linter feedback "can't translate into tolerable rust because of x, y and z". C people could look into that, and once the code is translatable into good rust, why translate.

If that was an outcome of the project, some people might find it easier to describe their solution in runnable C and let the "translator/linter" guide them to a non-broken approach.

I'd certainly consider all these positive outcomes quite unlikely, but isn't it pretty much the job description of DARPA to do the occasional dark horse bet?