Since I went through the exact same fretful thought process as you, I've since been wondering if we're just overthinking things, and meanwhile our snakes are just ... going whenever they feel like it, as snakes do. During my most recent photo session with Iggy (the one with the miniature tea sets), he was getting a fair amount of exercise as he slithered among the various props ... and right when I put him in my lap while I moved some things around, he let loose enough poo to make my pajama pants and the surrounding carpet look like a Jackson Pollock painting. An extensive clean-up ensued.
Afterwards, I checked my notes to see how exactly he'd saved this up. He'd been producing urates at regular enough intervals (inside his enclosure) that it hadn't raised any concerns, but when I looked up the last time he'd had a proper poop ... it was 3-4 months ago. I also checked his weight difference, since I'd just weighed him the day before. The bomb he dropped on me was 50 grams' worth of poo. No feeding or behavior issues, no straining or prolapse, no soaking involved, and still a very perky (though visibly deflated) snake after the deed was done.
Was there a moral to this story? Honestly I'm not sure. I guess I'm saying that your husbandry is probably perfectly fine, and Noodle is just ... being Noodle.