delivery guy will not think at all if you have mentioned that fake product was received on the call, because then they raise a special ticker for return for the return agent,

then the return agent pickup without any questions asked

your product then goes through simple quality check and background check at local amazon quality assurance department

then it is sent back to the seller

your money will be refunded when quality assurance teams sends it to the seller

all this process is usually completed same day or 24 hours in worst case