The datapad is sparse on details, but what information is there, combined with what Collan already knows, leads you to the following conclusions:
When the Cron Cluster exploded, the populated planet of Ossus was devastated. 99% of the inhabitants were killed. Those that survived were limited to a subsistence-level existence. With no ships and no communications - indeed no technology of any kind - the survivors gradually reverted to a primitive lifestyle. The survivors were, to a large degree, Jedi, so the Jedi code became deeply embedded in the tribal society that grew from the survivors. They are normally a peaceful people, but revere the extensive Jedi ruins on the planet as holy ground, and will defend them with violence. They would be classed as 'near human' as a species, and likely speak a dialect of Basic. As their forebears were almost exclusively Jedi, most of the Ysanna are force-sensitive, and many will have Force powers.