This is the last release compatible with OBS 27:
Additions: Improved the date condition: Added the option to select "before" and "after" for time of simple date view. (1) Added the option to ignore time component in the simple view. (2) Displa...
github.com
What happens if the camera is "off"?
Which source type are you using?
Does it show a black image / does the image freeze?
If so you might be able to use the pattern matching functionality of the video condition to detect that state.
I am unfortunately not really familiar with the downstream keyer plugin or the obs-midi-mg plugin.
The advanced scene switcher also supports the action to send hotkeys signals to OBS, but I understand you don't want to use this right?
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Maybe you can utilize the "Source" condition's "is showing" check to determine if a source
which is part of the downstream keyer is currently visible?
View attachment 94493
I hope that helps somehow!