It probably would have been a better choice if you had waited to do the introductions until after you had the male neutered.
You probably are hearing some mating going on. Be sure to check your gliders daily for any mating wounds. The male often holds the female on her shoulder using his teeth which sometimes can result in an injury that needs immediate vet care.
You may want to educate your self on breeding and taking care of joeys. You have no way of knowing that these gliders are unrelated so you need to be prepared for joeys that may have health issues related to inbreeding.