@sunny-lau
Thank you so much for this post, it gave me a new idea.
I also have an unresolved Wifi issue and now I think the reason of my problem might be similar.

BTW when you turn on that Iphone AP and try to scan Wifi with your Omega2+ you would see this on the serial console

[ ...] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: 8771d944
[ ...]
[ ...] Rebooting in 3 seconds..

and after that your Omega2+ goes into a frozen state.