@gingerdelmarco

If I may add:
Regardless of whether or not your daughter's issues are officially "caused by" SIBO or something else, it does seem that experimenting with diet is the most straight-forward way to claw-back some quality of life. Of course, this is a huge hassle to do, especially since she is at an age where she may be trying to life her adult life for the very first time. She already may be doing this, but my recommendation would be to try to do 2-4 days of a strict elimination diet testing one specific hypothesis, followed by however many days of eating at her baseline so that this doesn't become a chore. The whole time she needs to be logging what she eats, and reflecting strongly on how she feels and whether there is a positive/negative change.

Good luck again.

@gingerdelmarco please be aware that antibiotics will destroy all the good gut flora, as well as the bad guys. A good probiotic may be needed to replenish and that takes a few months.