Apparently, the client mode of the WiFi adapter configuration does not support hidden (non-broadcasting) 2.4GHz Wifi SSID's. I found an old listserv post from 2017 mentioning this topic once, but it doesn't seem there's ever been a fix for it? This problem is true for the base version 3.3.001 code and even the latest 3.3.001-282 edge build the same issue exists.
Anyone have thoughts other than enabling SSID broadcast on wifi routers I may not have control over?
Can you try to 'force' the connection, using the MAC address of the wifi access point?