I have an Arduino UNO with W5100 Ethernet Shield and NRF24L01+ configured as a MQTT Gateway and I can communicate with the MQTT Broker. However, I cannot communicate (via the radio) with a humidity sensor.

Debugging is turned on in MyConfig.h
I have tried multiple NRF24L01+
I have tried powering the gateway NRF24L01+ from another arduino uno (just using it as a power supply and connecting the grounds of the 2 boards).
I suspect I have a mismatch between the wiring and the software, but I am new to this and nothing I have found by searching the forums as led me to a solution.
Please help.

For the MQTT Gateway,
The NRF24L01+ is wired through the Ethernet shield to the UNO as follows:
GND to GND
VCC to 3V3
CE to 5
CSN to 6
MOSI to A1
MISO to A2
SCK to A0
IRQ not connected

The defines in MQTTGateway.ino are as follows:
#define RADIO_CE_PIN 5 // radio chip enable
#define RADIO_SPI_SS_PIN 6 // radio SPI serial select
#define RADIO_ERROR_LED_PIN A2 // Error led pin
#define RADIO_RX_LED_PIN A1 // Receive led pin
#define RADIO_TX_LED_PIN A0 // the PCB, on board LED */

The relevant parts in RF24_config.h as follows:
#define SOFTSPI // Requires library from https://github.com/greiman/DigitalIO
const uint8_t SOFT_SPI_MISO_PIN = 16;
const uint8_t SOFT_SPI_MOSI_PIN = 15;
const uint8_t SOFT_SPI_SCK_PIN = 14;

When I start the gateway, I get the following output:

Started!
0;0;3;0;9;read: 0-0-0 s=0,c=0,t=0,pt=0,l=0:
0;0;3;0;9;version mismatch
0;0;3;0;9;read: 0-0-0 s=0,c=0,t=0,pt=0,l=0:
0;0;3;0;9;version mismatch
0;0;3;0;9;read: 0-0-0 s=0,c=0,t=0,pt=0,l=0:
0;0;3;0;9;version mismatch

When I start a humidity sensor which is wired (triple checked) and programmed per the instructions, I get the following serial output:

send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
sensor started, id 255
req node id
send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
req node id
send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
req node id
send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
req node id
send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
req node id
send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
req node id
send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
send: 255-255-255-255 s=255,c=3,t=7,pt=0,l=0,st=fail:
req node id
send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
T: 20.00
req node id
send: 255-255-255-0 s=255,c=3,t=3,pt=0,l=0,st=fail:
H: 34.00