@Joanna I don’t know about the Mac version but the -wal and -shm files are only present for a running database (or one that has crashed), i.e. if PL5/6/? is running then you should expect to see them and if not present you are looking at the wrong database location (can you specify the database location on the Mac as we can on Win10?)!
If PL5/… is not running then you should only see the .db file (and any other detritus you have left behind in the database directory). In the image below PL5 is running and the database is located on an NVME (which is not the boot disk).
Don’t edit the database but so long as you only open it read-only any suitable SQLite software will help give an insight into what is going on, if you are database/SQL literate and “bored” with editing images and want to “waste” great chunks of (my) your life!