WAC510 5ghz Connectivity issue

There is one device only listed in the log,  5a:6a:91:ea:82:b3 - the AP does say in info-[5A-6A-91-EA-82-B3 wireless client could not obtain IP address], following a complete four way handshake - perfectly correct.

Have your DHCP somehow configured to assign IP addresses to known MAC addresses only? Due to Apples **** Wi-Fi privacy MAC address randomisation  and modern Android following the same "trend" - making it difficult (or almost impossible) for average network admins.

A factor in this issue is your wonderful idea configuring different SSIDs by AP, probably paired with Netgear's or other router makers Access Control or MAC Filtering with the access rule "Block all new devices from connecting". With this setting, if you add a new device, before it can access your network, you must enter its MAC address for an Ethernet connection and its MAC address for a Wi-Fi connection in the allowed list.

In some cases, your device will change its private Wi-Fi address. (more and ne fun and pun!):

If you erase all content and settings or reset network settings on the device, your device will use a different private address the next time it connects to that network.

Starting with iOS 15, iPadOS 15 and watchOS 8, if your device hasn’t joined the network in six weeks, it will use a different private address the next time it connects to that network.

And if you make your device forget the network, it will also forget the private address it used with that network, unless it has been less than two weeks since the last time it was made to forget that network.

At the end of the day, it's your own private network. There is no reason to make the network administration difficult or cumbersome. You know which devices are connecting, and what MAC addresses these units have (just like the serial number of the mobile phone SIM card which never changes for the obvious reasons - but having the same privacy issue Apple and the privacy freaks are having. So for your own network(s), you can safely disable the randomized MAC usage, and let the system use the device MAC for each of your own new wireless network name (SSID) added.