Coronavirus requires droplets to spread. Those droplets can be very small, and carry a ways through the air (which is what this article is proposing, not that the virus was carried through the ducting), but they are orders of magnitude bigger than the virus itself, and would absolutely be caught by a typical filter.

There are viruses that can spread that way. Measles, for instance, is known for doing that. Coronavirus can't (as far as anyone knows, and we know quite a lot about that).