I had the same issue.
Good news, changing my new Aeotec to ZigBee Channel 24 (from 25) allowed it to pair.
Bad news when it paired, it would show battery but never show status of motion just the broken cloud symbol. I had a spare Iris motion so I just replaced it with that.
But I still have it in case you have questions.
Also to get them in pairing mode you have to hold down the button for like 5-7 seconds until the red light goes out, then press the button one more time quickly and that seems to put it into pairing mode, the device doesn’t really give much feedback while it is in that mode you don’t know if was successful until you see the app give you that blue check box