Mackie Showbox - How to map proprietay UART interface to Control-Surface?

[T-vK]

I have reverse engineered the Mackie Showbox which basically is a PA speaker with built-in digital mixer and a removable controller that controls the mixer.

It's using a complicated proprietary UART-based protocol carried over RJ45 / Cat 5. I have now reverse engineered it to the point that I'm able to intercept the communication and take control over it using an ESP32:

Now I'd like to add MIDI support and Control-Surface theoretically seems to offer everything that I need. But I see no obvious way how I could connect the two because I don't have all the buttons and knobs directly connected to the ESP. I can only listen for incoming packets for example telling me that the gain or volume on channel 3 was changed to 3dB. Or I can inject a packet changing a specific setting.

Any advice on how I could achieve that?