So, Viola probably did something to Reene in order to get at her out of jealousy, since she likely has the hots for Noche and is being generic rival for his affection that is being directed at Reene. As for what exactly it is she has done, it's most likely to frame Reene as either the one that has done the attack (make Reene see a dream of sorts, make her feel as if she did it whereas it was Viola, is one potential way of doing it), or she at some point hypnotized Reene (kinda like the priest with his compelling words ability, but sneakier) and made her do it during her 'sleep' in a state of half-consciousness.