Yes, Rin is likely to be redeemed. That's more of a meta call in my mind, though, because it's a common theme to never involve categorical antagonistic characters who are "bad" for its own sake. I would argue this chapter creates depth for her character, but whether the reader sympathizes with is an individual judgment call. As of now, all we know is the lead-up, and then the aftermath with Ruka from Ruka's perspective. We have no real information at this time as to why Ria targeted Ruka, only that she left Ruka changed for the worse in her wake (as showcased by Ruka's behavior up until Suuna entered her life, and the tonal shift in who she was versus who she now is).