It can take more than 30 days for the hormones to dissipate. Having a female nearby can incite him to mark more. Many gliders nip while "grooming" you, and I know it can hurt a bit. Do be careful to use the same handsoap as scents can also increase the amount of biting he does. He may not nip at her, but like any intro, you have to go slowly and watch. If quarantine for her is over, you can start to swap pouches between the cages. That will take some time. Hopefully, they will start to "talk" (click) to each other. Then you can move their cages closer and eventually work up to a face to face. Just take everything slow and watch their reactions. Neutered males can still try to mate and can inflict mating wounds.