Fertilizing an egg using artificial sperm made from another egg is possible and has been tested on lab rats like a decade ago. Which means that even in the event that all males go extinct humanity could still survive.
While the sperm bank/donor options are the realistic choices today, given we already know they can engineer humans and as said Prospera cloned her own daughter we can readily assume it would be easy to produce and implement artificially produced embryos by their time.
On a more tangential approach, it could also be an induced form of parthenogenesis. Though in that case the child would purely be Miorine's then genetically. Recently there has been some breakthroughs in understanding how the process works, though specifically in fruit flies where they actually isolated a gene that triggers parthenogenesis in one species of fruit fly. They introduced that gene to another species of fruit fly and it successfully enabled it in the other species proving the gene was responsible for parthenogenesis. Of note, the gene in fruit flies only activates if there were a lack of males for there to be sexual reproduction, thus enabling asexual reproduction as a fall back behavior.
