... Anyone know what I may be doing wrong?
Probably nothing. Isn't Home+ a third party app? And don't your Roku devices show in the standard Home setup by Apple? If that's the case, that indicates it's an error in Home+
Of course, recheck the Home+ documentation to ensure that any special instructions they offer are followed, but if Apple Home sees it, and the Home+ app doesn't, that points to Home+ as the problem.
Roku Community Streaming Expert
Note: I am not a Roku employee.
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