well then hold up i hava a solution for ya...do this and you will get it..
[GUIDE] Unlock bootloader of Lenovo Tab 4 10 with OEM unlock "greyed out" (TB-X304F/L and other Qcom tablets)
WARNING: DO THIS AT YOUR OWN RISK !!!! I AM NOT RESPONSIBLE IF YOU START CRYING INTO YOUR BRICKED TABLET This guide is only for devices with "OEM Unlocking" option greyed out !!! Others can follow the simpler procedure mentioned in the TWRP...