How to determine device information on wifi devices

Hello.

I have read this article - Enable 'Device Detection' to allo... - Fortinet Community

which describes the method of locating device information, seemingly only for LAN,DMZ, and Untrusted.

To fully be able to block non essential devices from accessing our wifi, or 'managing' those devices thru qos or restrictions I need to be able to determine what those devices are.  For example, occasionally we might have users try to bring in their own personal devices to work 'outside' our security parameters. 

On the previous firewall I was able to determine those types of devices, like apple watches, ipads, other laptops, etc - and since i could determine their mac address, and knew their 'types' I could block those devices from our environment.

I don't see how to do this using the fortigate, managed switches, and managed wifi devices.  I can see only their mac address - and technically, according to the article above - i shouldn't have 'device detection' set on our wifi vlans. I do have it on the 'ports' and it's helpful in determining machine names, types there.

also - only some of my ports are showing the device identification (desktop...., laptop....) and some ports are not displaying that information.  I would think that the identification information is coming from the device but don't know what specifically differentiates or determines whether to display that infomation there so any thoughts on this would help.

is there a way around this so i know that only 'trusted' devices are using our wifi for business purposes?

thanks in advance.