To remove the staining to the lace, a great product is Goldwell Color Remover.
You could apply it to the lace with a Q-Tip.
Its more gentle than bleach & doesn't harm the hair knots, so no shedding.
You could also use it to take the dark tone of the dye down a bit and lighten the hair.
You only need to mix up a tiny bit at a time, so it lasts.

I'm really sorry to hear that she botched things up for you.
But maybe her mistakes have helped show you what NOT to do and I admire that you're determined to put it right yourself.

There is no problem with you detaching yourself right away as long as you've got the right products to loosen the tape and clean up afterwards.

Best of luck & keep us posted!