Personally I think your done !! Having a 3.5 yr old pee on the floor would be a lot to deal with !!! The time spent cleaning ect !! I agree with the pull up !
I am right now lavishing a ton of praise and stickers on a potty trainer , I would suggest ignoring her and her potty training issue altogether ! But it's not just the potty issues , if she is causing that much disruption to your dayhome , I would say term immediately !
I persevered for 6.5 months with a similar situation and the first morning dck was gone my group and I were a lot happier ! Dck was occupying so much of my time with neg attention I didn't even notice ! Once dck was gone ?? I could focus on all the dcks !!!
Speaking from experience I was so much happier !!!