I decided to hack my Dragino LG01 to make works properly on the TTN.
The problem of this version it’s has an MCU between the RF module and the Dragino motherboard.
I solder some wires and ‘disable’ the MCU, now the Dragino talks directly to the RF module.
It’s needed a new firmware, so I used the firmware from the LG02 version, and everything works.
It’s still a single channel but downlink works properly.