It's a really hard choice to make. I had an episiotomy that tore further with my first and it was third degree.
Cs wasn't offered for my second but I was warned of the risk of tearing again. Thankfully I didn't tear at all second time around and only had a first degree tear third time.
It's a totally viable option for her to have a vaginal birth as long as she knows there is a possibility of it happening again.
It really is a personal choice. For me I would have chosen vaginal anyway if a cs was offered as cs is a major operation and I would have likes to take that chance of not having any stitches at all.