My friends panther laid a retained clutch and only 1 egg out of them was infertile, she laid them 7 weeks after the first clutch.
3 weeks is WAY to early to be thinking of reintroducing them, my veiled laid a almost 5 weeks ago and she still shows unreceptive colours, although I dont mind breeding this female when I feel like it as she only lays small clutches in the 30`s and she has only ever laid 2 clutches and is 3 years old. But she looks like a 1 year old