Chunji's Ethos would still function well, as it'd seem enough time has passed since he used it last to where his brain has caught up from when his vision was used during attunement. He would be able to see a change in the flow of the leyline just under the ground near where the burn mark is, where it almost seems like a miniature leyline fountain has started to converge, swirling about. Though with each passing second, it's seeming to unravel, as if it were a tied knot coming undone, slowly back to its original self. There would also be a lingering mote of essence near the wall of the alley.
As for people, there would be people walking about the academy city outside the alleyway, down the main street, but nobody that would necessarily stand out to Chunji - certainly nobody that stands out immediately as suspicious.