Hilary ~ My research suggests that the answer is: Yes, but the mic has to be wired (not Bluetooth) into your iPhone's USB-C port — which wouldn't be practical for a distant 'platform speaker'. But whilst you await possible other answers from fellow users here, consider also asking Apple:
How to contact Apple for help with accessibility features
...Or ask this AI-powered search engine:
https://www.perplexity.ai/
...Cooy & paste your question into the 'Ask anything...' text box there:
I use Live Listen to listen to a live person on my MFI hearing aids. It works well, but I'm reluctant to hand over my iPhone to the platform speaker. Can I pair my iPhone 15 with a remote mic and get the same effect? And if so, how and can you suggest a suitable mic?
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