You're welcome. I just added an update to my post. I found out this evening that the Opple button controllers that do show up in HomeKit with the Aqara HomeKit Hub, do not show up in HomeKit when paired with the Mijia Multimode Gateway. For me, this is a huge disadvantage that I hope they change. It's one of my favorite controllers, so I'd be pretty bummed if I didn't already own the Aqara HomeKit Hub. Get the Aqara HomeKit Hub if you think you might consider one of those controllers at some point. I can't say that they'll never allow it to show up in HomeKit from the Mijia Multimode Gateway, but they definitely don't right now.
By the way, the Aqara HomeKit hub is on sale for just $34 USD for the next 12 hours. It's the Chinese plug version (they included an adapter when I bought mine), but it's otherwise the same as the US plug version. It is ETL approved and fully compatible with North American 110~120v 60Hz power.
You can also buy the US plug version from Amazon for $50 and get it faster. Plus you can return it to Amazon much easier if you don't like it.