unless aria physically stopped mielle after turning back time, i'd say what asher did worked in aria's favor. it really depends on how far the hourglass goes back because aria was screwed from the moment she answered mielle.
if the hourglass turned time to after aria answered mielle, mielle could have still pushed her father down the stairs and blame aria, stating that aria ran into room in hiding after the crime. or aria could try talking her way so mielle's dad would leave aka therefore foiling mielle's plan, but mielle could impulsively push him down the stairs still. imo the only way to stop this is if aria gets physical with mielle to stop her from pushing mielle's dad, which would obviously look bad in front of him and doesn't seem like aria's style in the first place
if the hourglass turned time to before aria answered mielle, mielle still might know aria is in her room and go on with her scheme again considering guests at the party have already seen aria and guests may have communicated that to her. if she doesn't know aria is in her room, then mielle might not do it, and aria would essentially be saved... but it would be less exciting narratively imho
tldr: i'm not sure how aria would have gotten herself out of this situation in a way that would be exciting to readers and she was also sorta screwed the moment she answered mielle. the hourglass imo wouldn't help that much
aria starting a conversation with mielle's dad would still allow mielle to go with her scheme since she could just completely cut off their conversation by pushing her dad down. the problem lies with the fact that mielle's dad is already there at the top of the staircase and mielle knowing aria is present allows mielle to frame aria anyway. the only way aria is safe from being framed is a) mielle truly doesn't know aria is there, therefore having no one to frame or b) the scenario that happened thanks to asher
OK HEAR ME OUT, I know that I should've been feeling romantic excitement during the latest scene but OH MY GOSH DID IT MAKE ME MAD ASF. Like this freaking prince