@alexsh1 Thanks, though I'm not sure you understood exactly what I'm saying.
If I connect the radio to the RPi 3 following the NRF instructions and using the NRF2RFM69 adapter, it is NOT working.
For it to work, I MUST connect the "IRQ" pin of the NRF2RFM69 (which corresponds to RFM's D100 pin) to RPi's pin 22 (which is where CE is supposed to go, according to instructions) and leave CE unconnected.
So if someone is using the NRF2RFM69 adapter and tries to connect the radio to the RPi 3 as if it were an NRF, it won't work. I think this is confusing and that's why I posted it.