Hi there, firstly your set up looks amazing. I'm sure your hamster loves it.
Maybe you have a
ghost hamster.
Consider taking your hamster to a vet (with experience in hamsters) to rule out any health issue.
My hamster is mainly motivated by food so I am feeding him a variety of small amounts of fresh fruit and veg, dried plant forage from petshop, that is what gets my hamster interested.
Get a pop up playpen. Put your hamster in the playpen with tunnels and some sunflower seeds.
Sorry if you've already tried this.
Sometimes they wait until the lights are out.