Yes, if this material is diamagnetic without being a superconductor it is by far the strongest such material we've ever found. 15x stronger than pyrolitic graphite.

From what I heard, it would. This kind of diamagnetism would be strong enough to be potentially interesting in other applications and research, if it turns out not to be a superconductor.

Not over a single dipole magnet. The "shape" of the field wouldn't make it stable, you'd need to add other magnets or a piece of string to stabilise. As I understand stable levitation over a dipole magnet is indicative of flux pinning which is a property exclusive to type II superconductors.