You'll probably find him, whether it's by looking or by 'accident'.
I lost my corn for 9 days, absolutely turned the house upside down, checked everywhere I could check (multiple times), left out food, heat, did the grocery bags along the walls and cornstarch for tracks thing.. nothing. After giving up for a while and then one night deciding I'll look again, I found her in the one spot I didn't get a good look into. We had an unused boombox sitting on the floor by her tank and stand - which I did check - however she was in the speaker the whole time
I was lucky I even found her as it is very hard to see inside the thing, and impossible to take apart. She just happened to move her head near one of the gaps as I had my eyes there.
Was your snake due for a shed by any chance? I believe one of the reasons my snake did not leave her hiding spot for anything was because she was about to shed. Once she did (the very next day) she came out. Luckily I found her when I did or she could have moved to places unknown within the house.
Just do some searches and read everything you can on the subject, you're sure to get some tips. I know a lot of the things I've read about escaped ball pythons is that they don't tend to go far, even staying in the same room they escaped within. Snakes are very good at making themselves invisible
so make sure you do a real good check, and it helps to think like a snake to get an idea of where it may have gone. They like to crawl along walls and not be out in the open (especially if you have other animals). Keep checking the warmest areas of the house as well.