That last page there, that's pretty much true. Because Hiiro got stronger naturally and through experimentation, WN Hiiro was already nearly as strong as Aquinas and could use way more combinations at this point in time. Also there was a time skip that justified him becoming that much stronger too. It was Implied that he had been traveling for almost a year before arriving in Xaos. During that time he separated from Red Loli at an undisclosed point and he then managed to surpass her level afterwards