  Recently, Bonanno et al. (2024) presented an explicit metric describing the
exterior of a collapsing dust ball within the framework of asymptotically safe
gravity. Based on this metric, we investigate in detail the properties of the
quasinormal mode (QNM) spectra for test massless scalar, vector, and Dirac
fields. We find accurate values for the fundamental QNM frequency and the first
overtones, demonstrating the appearance of a peculiar spiral-like behavior of
the overtones compared to the fundamental modes. Additionally, we study black
hole shadows and show that they align with EHT observations. Finally, we study
the grey-body factors and provide explicit lower bound estimates.
