Longer updates: So I did get a chance a few days ago to take the top off of Wally's hideaway and saw that he had actually totally hollowed out about 3 chambers so that he had a bigger ceiling to his sleeping chamber in the lower corner (since the hideaway is on stilts). and then totally stuffed up the front chambers with bedding as shown in earlier posts to cover those entrances. I'll have to get a picture at some point. I found some of his poops near his hoard/ sleeping area, though I didn't feel any damp spots. It could just be that he hadn't peed in awhile and that bedding (combo Carefresh/clean and cozy) is just really good at absorbing), but I switched out some of it anyway and will check it periodically.
He's become rather sedate in the past week- he stopped using his wheel, which I didn't realize for a few days, and only comes up a few times a night, during which he explores all his tunnels and corners and food gathers and then goes back to his chamber. 2 nights ago I started leaving some snacks in his silent runner to see if that will tempt him back to it. He hasn't shown any sign of illness, but we've had colds, so for all I know he's got some low energy like us this past week- or it's just his MO as a large male Syrian
Since the time change here in the Midwest we haven't taken him out as much between 6 and 7PM. Part of it is that we've been busy or sick, but part of it is that with the time change, it's still been pretty bright around then- not really dusk even, so I didn't think he'd want to come out, plus since he plugged up the entrances to the hideaway, it's harder to tempt him out with food. His entrance, which he created, is a long, narrow tunnel that actually rounds one corner of the cage before descending to the bottom of another corner where his next is.
However, that hasn't proven to be too big a deal because he's started waking up between 10 and 10:30PM regularly, which interrupts our reading time, but we're still awake. We've taken him to a new play area we created in our office, which he seems to enjoy more than previous areas and we can make it bigger and safer. There's an old shag carpet and we put up cardboard walls.
In spite of being less active while he's awake during the night (explores everywhere, just not using the wheel), he hasn't shown any signs of stress or unhappiness. In fact, he seems so comfortable with coming out of his cage now (though he never
asks for it the way some hamsters do), that if we put his igloo transport near him, he will climb right in even if we aren't using a snack to tempt him. So that's been a fun update. It only took 4 months, but he seems wholly comfortable with us, even though his personality is more independent/ reclusive. Not sure if reclusive is the best word, but if you've seen my other posts you probably know what I'm trying to describe.
Addendum to my daughter's post: I'm pretty sure "he did not want to be held as much as usual" is her magical thinking. He's never been all that comfortable with being held. He will now sit comfortably in my hands for about 15 seconds at best, which I'll admit I really enjoy, and he does seem to genuinely relax now and trust me. She has smaller hands and hasn't quite mastered the gentle cupping hold that I use, so he never lasts very long in her hands, but we're working on it

Our play sessions usually involve sitting and watching him in the play area with a few pets and quick holds here and there.