Stephen,
this is definitely a bug. the symptoms seem to be changing based on choice of compiler, MPI library, and compiler flags. it seems to be coming from inside the RCB load-balancing algorithm, where some data structures keeping track of what data to send to what MPI rank gets corrupted.
as a workaround, i would suggest to either avoid fix balance or tiled communication. you are using a rather unusual combination of settings, so it is more likely, that this bug went unnoticed so far.
would you mind filing a bug report with the example input at the lammps github project at: https://github.com/lammps/lammps/issues ?
thanks for providing a small and representative input deck,
axel.