Hello @Mnfish22 & @Joey_van_der_Gaag,
Peplink/Pepwave products do not currently support tethering by USB of iOS devices, there is a feature request found here, feel welcome to add your vote if you like.
In regards to Windows not tethering with iOS devices, ensure you have the latest version of iTunes installed, it has the drivers required that may fix your PC tethering USB issues. We use iPhones (both our own and clients) a lot for support in Australia and not having iTunes up-to-date is one of the first things we often need to get sorted with doing support tethered via USB to an iOS device.
Happy to Help,
Marcus 