linkKeyExchange = “no” should be set, because otherwise a lot of devices won’t join the network, a lot of them are ‘legacy’.
You might need to reset the lamps in order to make them join the network.
As for the ONOFF, it might be the case that you have a device that exposes two end points, one for each switch. If that’s the case, the ZigBee module should create two peers, one for each end point.
As I didn’t have available such a device (with multiple end points like that) to test, I cannot be sure that it works as expected.
Of course, I cannot be sure that is the case with your device, I would need a log with the device pairing to figure it out, with debug level turned to something like 7.