I think the question was why whoever picked it up didn’t do anything with it, which points towards it not just being an issue of incompetence, but maybe an underlying issue of the technology.

It's super common for UP to be sold for $1 to someone who has no intention to use it, just to have a larger defensive IP portfolio.

Or a commercial blood bank bought it. Since this was based on cow hemoglobin and thus a thread to their business model.

Or a patent troll, who are now busy working out how they can sue the Japanese scientists.