Home Devices sync to Macbook and old Iphone, not iPhone 18 or iPads

My existing Apple Home network syncs on my Macbook and on my previous iPhone 14, all devices show up but it doesn’t appear on my new iPhone 18 Pro Max or on either of my 2 ipads. All show the exact same Apple Account email and photo, and other iCloud data, including passwords, sync normally. All on latest ios. It's as if I'm logged into 2 different icloud accounts.

I've signed in an out of icloud with the new phone and ipads (I'm reluctant to sign out of the devices that are currently synced properly). I've deleted the Home app from the new phone and iPads and reinstalled fresh Home app. Disabled and reenabled Home app syncing in the iCloud section of settings.

Restarted both Apple TVs (hubs) and routers.

Iphone 18 and both ipads just show a default My Home set up, which shows me as the owner/resident on correct iCloud account but doesn't show any devices or hubs.

When I change the name of the Home from my Macbook, the name also changes on my old phone but doesn't change on any of the iPads or the new phone.

What could prevent only Home from syncing, and how can I restore access without deleting my existing Home setup if possible?