usb-modeswitch is not needed, kmod-usb-serial-option is required.
These commands need to be run once:
AT+QCFG="usbnet",1
AT+QCFG="nat",0
AT+QICSGP=1,1,"apn"
AT+QNETDEVCTL=1,3,1
AT+CFUN=1,1
Replace apn with your APN name.
Correct syntax is AT+QENG="servingcell"