This post should help you get the CLI and run logs (as well as other commands).
Basically, once you have the CLI available on your machine this command will start logs:
smartthings edge:drivers:logcat
You’ll be prompted for your hub IP address, so make sure you know that, and you will choose the Roku driver from the list of installed Edge drivers. Press Ctrl-c to cancel logs at any time.
What you should do is fire up logging, then run discovery. Capture the log and paste back here, and be sure to surround the log text with triple backquotes (```) both at the beginning and at the end. This will help ensure readability.
EDIT: To prevent this topic from filling up with log dumps, please send me a direct message with your log.