The charges against Jane were state charges, he committed no federal crime. He would need a deal with the California authorities, not the FBI.
The FBI doesn't have jurisdiction in non-extradition countries so they wouldn't have been able to arrest the drug dealers at the hotel.
Patrick wore his wedding ring for about 20 years without ever taking it off. Always lived in a sunny place (California, Mexico). Then, when he removed the ring, a white line should have remained on the finger. But there is none.