Well. I think I’ve conquered it.
I decided to, even with my limited skill, go with my hunch regarding disabling RP05, and kept at it.
I discovered a script on ArchWiki listed under Power management/Wakeup triggers - ArchWiki called wakeup-triggers that I could modify to ONLY allow my USB and power button to trigger wake up events.
Using this, my system all of a sudden will hibernate consistently with no problems.
Thanks everyone here for your efforts, I apologize if my info wasn’t detailed or clear enough. I feel like the last few days have been a learning experience though, and I feel more comfortable with the terminal than I ever have been before, so there we go!
Thanks, Garuda Community!