Typically on an HPC, at least with my experience with LSF is that the optimization jobs fail if there is no PSI_SCRATCH variable set to a storage destination with plenty of storage space. For example optimization of a molecule say of 60 atoms can create up to 10 GB of temporary space with binary numpy files for grids and other matrice storage. But it sounds like you already did this maybe, as I reread you post saying you are seeing optimization complete?
Maybe sure you have set PSI_SCRATCH to a variable in your bashrc as indicated for a similar wrapper poltype2 which only uses PSI4 to optimize ligands. Is your code published on github?
Typical things to check @loriab talks about here Strange crash on Psi4. In particular pay attention to her comment “Also, Psi4 won’t benefit from running under MPI. Its strength is intranode parallelism.”