Detect Camera disconnected?

I have two older cameras that are starting to get flaky. They are managed in Synology Surveillance Station, and they recently added a great feature that when these are disconnected for X mins it will automatically send a restart to the camera, which brings it back online.

The issue is the notifications from Synology are too frequent. I get one when the camera goes down and then once it’s automatically brought back up for both cameras. I don’t want to disable the notifications in case the camera goes offline for some other reason.

I had an idea to move the notifications into Home Assistant. That way I could say if camera offline for > X + 1 mins (longer than the Synology restart) then send me a notification. But it doesn’t appear there is any state to tell me this. When it’s offline I have no image in hass, but the properties are the camera are still “normal” (including, that the camera is streaming).

Is there some way to track this that I’m overlooking? Or is this a bug in the “streaming” state?