So my guess is both the heroine and Lana are transmigrators. That Lana only recently re-gained her past memories during your denunciation event. That all the things her husband invented at the request of the capture targets were things the heroine talked about wanting because she missed them from her past life.
Also, why does every isekai act like soap is some modern invention? There is evidence it was used around 2800 BC in ancient Babylon, the Egyptians used it, there is a papyrus dated 1550 BC describing it made, the Romans used it in there is evidence in Pompeii of it being mass produced. The Celts and the Arabs had it. A modern formula was patented in the 1800's but it's ALWAYS been around in one form or another. Hell if I wanted to I could make some using rendered cooking fat and some wood ash from a home fireplace, it wouldn't be the prettiest soap but it would get the job done.