SAPT as implemented in Psi4 can only compute interaction energies between dimers. As far as I know, SAPT has only ever been extended to trimer, but not to tetramer and pentamer. If you want to do three-body SAPT computations, you may want to look into SAPT2016.1.
If you really want to decompose the interaction energy of tetramer or pentamer, you’ll need to use another energy decomposition analysis. An example is ALMO-EDA, which is implemented in Q-Chem (have a look at chapter 12.5 of Q-Chem’s manual for an example), but there are a lot of other energy decomposition analyses schemes implemented in a number of quantum chemistry softwares.