According ST’s documentation, the power amplifier a LoRaWan gateway is expected to have is removed from this module. When multiple gateways receive an uplink, TTN will select the one with the strongest signal report - presumably the closest to send any downlink reply. But this gateway will not be able to transmit at the commanded signal level, so even if it’s a bit closer, a gateway with a power amp should be used instead - downlinks assigned to this one may simply be lost. TTN software doesn’t have any way to handle something that doesn’t have the capabilities that something registered as a gateway must have.
ST’s documentation says that this board is for evaluation only - it’s not a product intended for actual use.