Roku wireless speakers don't use bluetooth, no bluetooth speaker or headphone can be paired to ANY roku device directly. Roku are bluetooth receivers only, just like bluetooth speakers and headphones each has to have transmitter to communicate with, which none are.
If you have Roku tv, then the Roku wireless speakers paired to it would be the mains, they use wifi-direct to communicate not bluetooth. Then the TCL soundbar once paired to the roku tv will be the center channel.
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