I would like to note one more interesting thing regarding Domain Expansion though. It works by detecting Cursed Energy. Cursed Energy and Chi are fundamentally different. Chi is the life-force of all living things in Dragon Ball. Cursed Energy is information manifested into existence by negative emotions as opposed to being correlated to the life-force of living beings. Thus hiding his Chi shouldn't hinder the Domains Expansion ability to pick him up...
However, Ultra Instinct is purely instinctual. I suppose if you argue he holds no emotions while fighting, he wouldn't be detected anyway. I can't remember if Ultra Instinct removes some emotions, but I do know Goku can still think and experience feelings in Ultra Instinct. Heck, even Whis can, and their Ultra Instinct is far more refined than Goku's.
Dunno why I didn't think of this until now, but if verses are equalized, it kinda makes things funny if we treat Goku's chi as his "Cursed Energy" when it's fundamentally different... not sure how this ends up working out tbh. Just thought I'd bring it up.