For some history, I think I posted here once before, when I first got my big boy, Doodle. He had a myriad of issues we worked through from his breeder, such as scale mites (the topic of my thread I believe), stuck shed, poor diet, etc. He's been doing well since then - a big 2' long chunky boy. (I think he's a boy anyway!) He is 3 1/2 now!
Recently, when I cleaned out his terrarium and was looking at him closely, I noticed that he had an issue in between his little toe and the one next to it (the two exterior-most toes). The scales seemed to be parting from each other where the toe pad meets the scute-looking scales, leaving a whiteish gap. Nothing flaked off when I rubbed it nor when I washed it. Since I just cleaned his terrarium, I thought he might've had a hidden poo I didn't see that he was getting irritated from stepping in. I resolved to keep an eye on it and put him back.
Now, about a week or so later, I looked at his toes again and it appears to be getting worse. His other toes are now showing signs of these parting scales, and almost looks as if the black outer portions are flaking off.
None of his other scales are exhibiting this, his terrarium is clean and kept at mid-70s on the cool end, and 90s-100 around his basking spot (he tends to lounge on the hotter part, but moves around on his mood). His diet hasn't changed and his stools are healthy looking. My only thought is the humidity, as it is the winter months, it's very dry in my house. We moved this past February and this is the first super dry winter I've had to deal with. I have a humidifier with a meter that keeps his terrarium at 60% humidity, but it runs so much I have to refill the thing quite a lot, and I do miss it sometimes. I'm considering a humid hide, but I've never set one up before.
I did read the damaged/flaky scales section on the care sheet and I feel this post is a bit different as it has come up out of the blue, is actively getting worse, and is centered only on his feet/toes.
Below are some pictures of his feet.


Any help would be greatly appreciated. <3 Thank you so much in advance for your time!
Edit: The issue appears on both of his front feet, and might be starting to occur on one of his hind feet, to clarify.










