If you are using MQX try this:
enable HS driver
#define USBCFG_DEFAULT_DEVICE_CONTROLLER (&_bsp_usb_dev_ehci0_if)
#define USBCFG_DEFAULT_HOST_CONTROLLER (&_bsp_usb_host_ehci0_if)
And rebuild libraries.
This works on the TWR-K70 , try it on the TWR-K60
Also, In the USB stack, you need to setup HIGH_SPEED_DEVICE to 1 in user_config.h in each USB stack project you want to test with TWR-SER2.