The only Bluetooth remote Roku ever used was for the Roku 2 XS, and I don't believe those you have are it. I assume you mean RC-AL7. @Tivoburkee can give you the definitive answer, but I believe both of those should work on your Ultra. Any of the current remotes will work with any model Ultra. The simple remote is IR and the voice remotes are RF.
You might want to try harder to pair the ones you have. Make sure you have good, fresh batteries and it helps if the remote is close to the Roku when you try to pair.
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