Getting custody rights

So long story, don’t need any judgement but my fiancé has a daughter 5 months old. He hasn’t met her yet. He went to mediation yesterday and they want him to meet her and see her 3 times a week for 3 weeks, go to the mothers house alone give her baths and play with her... now we have a 1 week old and a 3 year old.. yes add the math he had an affair/we broke up for a bit... that I’m not needing any advise on... what i don’t understand is how unorthodox it is to go to her house alone for visits.. these should be in public places and also our children and myself should meet her considering I’ll be the one taking care of her when she is at our home. Also it’s going to effect our 3 year old. Plus the poor child needs to visit our home as well.. she’s 5 months old.. not going to know the difference.. you send your child to daycare for 8-10 hours a day without 3 visits a week before you start the care.. how is this different.. am i wrong?