"this PS4 is not the primary on my PSN account it’s the secondary"
That's why, when you're not on the console that designated as your primary or home console, a ps4, xbox or switch needs a constant internet connection in order to play your games. You're esentially game sharing on that second PS4.
This is the setup me and my little brother has where all of his consoles are registered as my home console and he gets access to all my games. And I usually have a constant internet connection so me having to be online at all times isn't a problem for me. On the very rare occasion my internet is off or having issues, I either play the few disc games I have or play retro consoles.