Regarding ITC ON INVERTED DUTY SUPPLIES REFUND IN BUS SERVICE PROVIDER

EXPERT I AM MUCH CONFUSE REGARDING REFUND IN CASE OF INVERTED DUTY STRUCTURE AS PER SECTION 54(3) IN CASE OF SERVICE PROVIDER OF RENTING A MOTOR VEHICLE.
SIR MY FRIEND PURCHASE A BUS AND PROVIDE FACILITIES TO A COMPANY FOR HIS EMPLOYEES.SIR HE PURCHASED BUS IN AUGUST 2017 WITH CHARGE GST @ 28% SIR HE IS PROVIDING SERVICE WITH CHARGE GST @ 5% (RENTING OF MOTOR VEHICLE) SIR HE HAVE ITC IN CREDIT LEDGER IN GST PORTAL AMOUNT IS APPROX 7 LAKH. SIR HE WANTS TO FILL GST RFD01 FOR CLAMING REFUND OF INVERTED DUTY STRUCTURE . BECAUSE HE PURCHASED BUS WITH GST CHARGE 28% AND PROVIDING SERVICE @ 5%. SO PLEASE TELL ME CAN HE APPLY FOR REFUND UNDER INVERTED DUTY STRUCTURE PLEASE REPLY????