Previously joined Wi-Fi networks will not typically appear under "Other Networks" unless they are currently within range and broadcasting their SSID.
- "My Networks": This section usually displays the Wi-Fi networks your iPhone is currently connected to or has recently connected to and remembers the password for.
- "Other Networks": This section lists Wi-Fi networks that are currently detectable and available to join. It doesn't inherently show a history of all the networks you've ever connected to in the past if they are not currently broadcasting nearby.
Where the list of all saved networks resides on iOS:
The list of all the Wi-Fi networks your iPhone has ever joined (and saved the password for) is stored within the system's configuration files. Unlike Mac, there isn't a readily accessible, single list within the Settings app that explicitly displays all of them when those networks are not in range.
How "Forget This Network" Works Even When Not in Range:
When you tap "Forget This Network" on a previously connected network, even if it's not currently visible under "Other Networks," your iPhone is essentially removing the stored credentials and configuration for that specific network from its internal list.

Investigate Configuration Profiles (as you mentioned): If your organization has installed a configuration profile on your iPhone, this profile could be managing Wi-Fi settings or pre-configuring connections. In this case, removing the profile might help.
- Go to Settings > General > VPN & Device Management.
- Look for any profiles listed. If you find one related to your organization, tap on it and see if there's an option to "Remove Profile." Be cautious when removing profiles, as it might affect your access to organizational resources. Consult your system administrator before doing this if you're unsure.
Unfortunately, there isn't a hidden menu or a more direct way within the standard iOS interface to view and delete all these historical Wi-Fi connections when they are not currently broadcasting.

If you are using a third-party app that manages saved Wi-Fi networks, and you are encountering issues, the best course of action is to get in touch with the app developer for support and guidance.
Third-party apps might interact with the system in unexpected ways, and the developer will have the most specific knowledge about how their app functions and any potential limitations. They might offer a solution or explain why the app isn't working as expected in your situation.