Actually, I do remember the Tsukumogami telling Yuu, Himeka and Galka this. On the day they learnt of each other (I believe chapter 2), the tsukumogami tells the group of Yuu’s wish to see Karin again, and told him whichever Karin he did not choose would disappear ”As that is her wish”. I might...
I believe it is stated that he prayed once everyday. The sequence of 3 moments only highlights how he did it from childhood until now. So yes and no, but I think the original point that the Karins are from different points of her life is valid to a point.