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The adafruit code appears to actually connect to the thermometer rather than just looking at advertisements, so I don't know how useful that is.
That's because data in advertisement is encrypted, see https://github.com/Magalex2x14/LYWSD03MMC-info#encryption When connected there is no such encryption! And any device can connect without pairing so it all makes very little sense.
That's why I suggested alternative firmware - there is no such encryption nonsense there. And the firmware was developed from scratch (with Telink SDK available on github) and is opensource.
The adafruit code appears to actually connect to the thermometer rather than just looking at advertisements, so I don't know how useful that is.
It looks to me like the advertising is using a different format to the one other Xiaomi thermometers use. It's probably better to do:
And then show us everything it prints over the course of a few minutes, with a rough idea of the temperature and humidity the device is showing - and we might be able to work out how to decode it then