I just got some additionial details about the ticket, and I don’t think we can fully rule out the Wi-Fi network yet.
As I understand it, you’re using a Deco M5 mesh system, with Homey Pro connected to one of its satellite nodes. The Dirigera hub is connected to the network via Ethernet.
That last part is worth double-checking: is the Dirigera hub connected directly to the main Deco unit, or is it plugged into one of the satellite Deco units? If it is connected to a satellite unit, then it is only wired to that satellite. Unless that satellite itself uses Ethernet backhaul to the main Deco, the Dirigera hub’s traffic still depends on the wireless mesh connection between the satellite and the main unit. In practice, that means it is not truly wired all the way back to the main network.
This setup can mean that Homey has to communicate over multiple network links before its traffic reaches the rest of the setup. The main Deco needs to maintain a solid connection to the satellite, and Homey also needs to maintain a solid connection to the satellite. If Dirigera is connected to a satellite without Ethernet backhaul, its connection also depends on that same wireless mesh path.
For general use, such as browsing or watching videos, this kind of setup can appear to work fine. Those use cases can usually tolerate brief buffering, retries, or small delays. Matter control is less forgiving, especially with a large setup of 60 or more devices and Matter Multi-Admin involved. Small drops, packet loss, or delays can have a much bigger impact there.
In the diagnostics report, we can see that the connection is being lost. After that, Homey tries to reinitialize the connection, but that process takes too long and eventually times out. That suggests the issue may not be the initial pairing itself, but the stability and recovery time of the network path. If the connection drops even briefly, Homey needs to re-establish communication before it can continue. If the network does not respond quickly and consistently enough, that recovery can fail.
You mentioned in the ticket that you tried connecting Homey to the main Deco unit but did not notice a difference. How far away is that main access point from where Homey is placed? It could simply be too far away for Homey to maintain a stable enough connection, even if it technically connects.
My suggestion would be to verify the actual Deco topology in the Deco app: which node Homey is connected to, which node Dirigera is connected to, and whether the satellite Deco units are using Wi-Fi backhaul or Ethernet backhaul. If possible, it would also be useful to temporarily test with Dirigera connected directly to the main Deco unit and Homey placed close to the main Deco, just to remove the mesh backhaul from the equation.