Could a Primordial Black Hole Explosion Explain the Extremely High-Energy KM3NeT Neutrino Event?

A black hole is expected to end its lifetime in a cataclysmic runaway burst of Hawking radiation, emitting all standard model particles with ultrahigh energies. Thus, the explosion of a nearby primordial black hole (PBH) has been proposed as a possible explanation for the ∼220 PeV neutrino-like event recently reported by the KM3NeT Collaboration. If the event originated from a PBH, the source would need to lie at (1-7)×10^{-5} pc-depending on the assumed effective area-thus within the Solar System. At such proximity, the resulting flux of gamma rays and cosmic rays would be detectable at Earth. By incorporating the time-dependent field of view of gamma-ray observatories, we show that LHAASO should have recorded O(10^{8}) events between fourteen and seven hours prior to the KM3NeT detection. IceCube and KM3NeT itself should likewise have detected of order a few hundred events in the range 1 TeV≲E_{ν}≲1 PeV during the 24 h preceding the burst. The absence of any such multimessenger signal, particularly in gamma-ray data, strongly disfavors the interpretation of the KM3-230213A event as arising from evaporation in a minimal four-dimensional Schwarzschild scenario.