Can you let us know if this is still an open issue and still an issue with SDK2.4.0?
Certainly suggest moving to SDK 2.4.0
To join a specific AP BSSID must be used.
An example of this is in the "console app" using the "test credentials" command.
test_cred <ssid> <bssid> <channel> <open|wep|wpa_aes|wpa_tkip|wpa2|wpa2_tkip> [key]