There is not an MX feature to disable this easily but there maybe a workaround.
Have you tried Enterprise Home Screen?
Here you can disable the top bar from being allowed to be used (and this restricts the access to the hotspot via there) Then you can set restricted settings (Im not 100% sure what that would mean on a TC55 ) would need to see if that solved it
MBFK48 might have some other ideas too?
Thanks for the reply - sadly that doesn't work as restricting access to the top bar prevents users connecting on to local wifi (e.g. in village halls on events). I'm using EHS now - just far from a great solution that its ether no user WIFI access and no Tethering OR User Wifi access and Tethering.. seems odd that such a basic requirement is not covered.off
Just wished I could switch off tethering all together there is no situation with these devices where I would wish for it to be used, and the consequences if some clever person does is expensive.