Thank you so much for taking the time to help me out here brocaar!
The output I got now made much more sense 
(with the panic output):
2023-07-20T19:23:34.964Z INFO [libconcentratord::reset] Configuring reset pin, dev: /dev/gpiochip0, pin: 23
2023-07-20T19:23:34.964Z INFO [libconcentratord::reset] Configuring sx1302 power enable pin, dev: /dev/gpiochip0, pin: 18
2023-07-20T19:23:34.964Z INFO [chirpstack_concentratord_sx1302::cmd::root] Starting Concentratord SX1302 (version: 4.2.0-test.2, docs: https://www.chirpstack.io/concentratord/)
2023-07-20T19:23:34.964Z INFO [libconcentratord::reset] Enabling concentrator power
2023-07-20T19:23:35.065Z INFO [libconcentratord::reset] Triggering sx1302 reset
2023-07-20T19:23:35.265Z INFO [chirpstack_concentratord_sx1302::concentrator] Setting i2c device path, path: /dev/i2c-1
2023-07-20T19:23:35.265Z INFO [chirpstack_concentratord_sx1302::concentrator] Setting i2c temperature sensor address, address: 57
2023-07-20T19:23:35.265Z INFO [chirpstack_concentratord_sx1302::concentrator] Setting board configuration, lorawan_public: true, clock_source: 0
2023-07-20T19:23:35.265Z INFO [chirpstack_concentratord_sx1302::concentrator] Setting up fine timestamp, enable: false
2023-07-20T19:23:35.265Z INFO [chirpstack_concentratord_sx1302::concentrator] Setting up concentrator channels
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring radio, radio: 0, enabled: true, center_freq: 867500000, type: SX1250
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring radio, radio: 1, enabled: true, center_freq: 868500000, type: SX1250
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Setting up concentrator channels
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring multi-SF LoRa channel, channel: 0, enabled: true, freq: 868100000, rf_chain: 1, if_freq: -400000
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring multi-SF LoRa channel, channel: 1, enabled: true, freq: 868300000, rf_chain: 1, if_freq: -200000
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring multi-SF LoRa channel, channel: 2, enabled: true, freq: 868500000, rf_chain: 1, if_freq: 0
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring multi-SF LoRa channel, channel: 3, enabled: true, freq: 867100000, rf_chain: 0, if_freq: -400000
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring multi-SF LoRa channel, channel: 4, enabled: true, freq: 867300000, rf_chain: 0, if_freq: -200000
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring multi-SF LoRa channel, channel: 5, enabled: true, freq: 867500000, rf_chain: 0, if_freq: 0
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring multi-SF LoRa channel, channel: 6, enabled: true, freq: 867700000, rf_chain: 0, if_freq: 200000
2023-07-20T19:23:35.266Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring multi-SF LoRa channel, channel: 7, enabled: true, freq: 867900000, rf_chain: 0, if_freq: 400000
2023-07-20T19:23:35.267Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring Std LoRa channel, enabled: true, freq: 868300000, rf_chain: 1, if_freq: -200000
2023-07-20T19:23:35.267Z INFO [chirpstack_concentratord_sx1302::concentrator] Configuring FSK channel, enabled: true, freq: 868800000, rf_chain: 1, if_freq: 300000
2023-07-20T19:23:35.267Z INFO [chirpstack_concentratord_sx1302::concentrator] Starting the concentrator
Opening SPI communication interface
Note: chip version is 0x00 (v0.0)
ERROR: Failed to set SX1250_0 in STANDBY_RC mode
ERROR: failed to setup radio 0
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: lgw_start failed', chirpstack-concentratord-sx1302/src/main.rs:114:80
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace