I am not an orthopaedic surgeon and although having had a bilateral hip arthroplasy many yeas ago, may comments are gleaned from colleagues.
First of all it is bad luck that you had a metal on metal hip replacement and subsequent repercussions.
You have two choices, a revision hip replacement or a Hip debridement and i think that your surgeon has given good advice based on your symptoms.
Recovery time is always difficult to prognosticate, but you are looking at a period of 2 -3 months mainly, during that time , on crutches.
Success?..that depends upon your surgeon......my experience 50/50 no better , no worse........just my opinion.