Any chance that some of the paper listed in the 8ks was sold through Nite? If they didn't actually have the paper on hand it could be listed as short. If it wasn't delivered right away it would come up as a fail to deliver. Although it might have been delivered the next week.
This would be a great way to get Ihubers to buy since they would be doing it for the typical Ihub reason - short squeeze (where it doesn't usually exist).