Hi Randy, the student just got back to me:
"Yes, the errors are in cluster std out/err files.
I tested that file (C:\Program Files\AnsysEM\Ansys Student\v212\Win64\schedulers\diagnostics\Projects\HFSS\MPI_tst2.aedt) just now and it worked fine. Then, it probably means there's something wrong with my file?"
I will ask for a copy of their slurm submission script, I have not done that yet.