Quinn was wondering what happened to Sil for a few reasons. First, learning that Vorden and, most likely, Raten was also still alive, gave him hope that Sil was as well, but that begged the question, where was Sil right now? And where was he during all of the chaos that had gone on? Did something unforeseen happen that made Sil unable to help his allies Or did he also disappear?
From what he had learnt, Sil had unlocked his soul weapon. Something that the Blades hadn't been able to do before. It was believed that they couldn't, but in the end, he was the one who succeeded, and with his powers, he was able to do some crazy things.
There were only two things that let Sil down when fighting, his lack of experience and the deficiency of Qi. However, he could improve both of these things over time, and after a thousand years, he was sure to be strong, that was if he had survived that long anyway.