OTBR/Matter and Apple/Google Home

[faint path]

I'm having some issues connecting either Apple Home or Google Home to my Matter/Thread enabled Home Assistant installation. My setup is working and Home Assistant can control all Matter/Thread devices just fine. I've made a connection to Google Home to control some of these entities using Home Assistant Cloud/Google Home integration.

However, I also want to connect these Thread/Matter devices to either Google Home or Apple Home directly. Reason for this is that my blinds are of the Eve brand and require either Apple Home or Google Home to connect to these devices in order to use the Eve app. The Eve app allows for additional settings/controls that the Matter integration in Home Assistant can't handle (yet?).

My setup:

Proxmox hypervisor 8.4.1 (clean stock install, no changes in /etc/sysctl.conf)
Home Assistant VM (based on Proxmox VE Helper-Scripts)
Home Assistant 2025.6.1 (HassOS 15.2)
IPv4 and IPv6 auto-configured in Home Assistant. Have valid pingable IPv4 and IPv6 addresses in the local network.
Have multiple subnets/vlans but for now everything related to this is in the untagged primary vlan.
OpenThread Border Router addon from official addon store. 2.13.0 (connected to SLZB-06M, in Thread-only mode, latest Fw, directly connected to same switch as Hass)
Matter server 8.0.0 (tried with option "Use the latest beta version" on and off)

Multiple Thread/Matter devices:

Eve MotionBlinds 20CAA9901 (85) (different models but mainly testing with this)
Aqara Door and Window Sensor P2 (8194)

My issue:
Everything is working fine in Home Assistant. It has clear line of sight to all Thread devices, was able to add everything to Home Assistant and can control all exposed resources. The blinds report their positions and can control their position, no issues. The Aqara door sensor is reporting the open-state of the door. All devices work great, no connection issues.

I've used the "share device" feature to share my Matter devices to other controllers, like Google and

Apple to connect them into their eco system (again, main motivation is to use the native Eve App for my blinds for extra non-standard controls/settings). At first both Apple and Google complained there was no Border Router available and redirected me to buy new hardware in their ecosystem. I have tweaked my mDNS settings in Unifi Router and now the proper _meshcop._tcp. mdns is being published on the network. I've tried again to add the devices to Apple/Google and the adoption now works. The devices get added into their ecosystems and the initial state is also reflected. It seems the device works but it doesn't really.

Clicking on it in Google Home shows a fallen ice cream and a generic unreachable error. In Apple it shows "Updating" followed by "No response". If you try to change the blind position, it tries to set the new position but fails after 10 or 15 sec and reverts to old state.

Clearly both Google and Apple can now read and adopt the devices but it can't actually update the values. I'm guessing there is still something on a network level not 100% here.. or can't the matter/thread implementation in Home Assistant as-is not handle this use case?

Thanks for any insights you can share.

To add to this: I can ping (4 and 6) from desktop computers and iPad to multiple endpoints (Home Assistant, Routers, IPv6 address of Matter devices etc) and this all works.

When I change the blind position in Home Assistant, the blind moves instantly. Apple Home now seems to get the new value within a few seconds. But setting a new value via Apple Home doesn't work at all. (But still shows Updating/No Response in other views).

[faint path]

Weirdly enough, I can control the blind in Apple Home within seconds after adopting/including it in Apple Home and the blind responds to that. So weirdly enough, that works. After 10 sec or so, it can no longer update it.

[trim crypt]

Is the SLZB-06M connected using USB ?
Using it with ethernet (or even worse, wifi) is a giant red flag

[faint path]

Ethernet mode. I understand the latency concerns regarding networked Thread radios but it's connected to the same switch. I doubt the OTBR addon and SLZB-06M connection is at fault here as the logs of Thread and Matter don't show any errors nor does Home Assistant ever lose connection to the Thread devices. Again, the native Home Assistant Matter integration can 100% always talk to my Thread devices. Control from Home Assistant dashboad is snappy and always available.

[faint path]

@trim crypt I just rebuild my Thread controller, this time via USB-connected SLZB-06M. No change in output. Home Assistant dash has instant control. Google Home can add but not see/use. Apple Home can add and see updates to the blind but not control it.