Surgeon will give you specific requirements. Mine required removal of all piercings, including face (I swapped them out for glass retainers). It has to do with electro cauterization and the risk is low but not absent. I’m guessing most surgeons want to reduce all liability as much as possible.

https://www.apsf.org/article/body-piercing-and-electrocautery-risks/

There is certainly a risk of burning from any metal object in or on the body except inert metals such as those used in prosthetics and dental work. Thats why even wedding rings are removed and if not able to be removed taped to prevent arching. I'm sure your surgeon will insist on her removing all her piercings and as a side note facial piercing may interfere with the anaesthetic process in obtaining a correct seal should they need to use a mask. Its all about risk minimisation.

Finally remember that the body is an excellent conductor of electricity being mostly water. It doesnt much matter where the current is applied.A

Ultimately you're going to have to ask the surgeon. It doesn't matter what anyone else thinks.

It would be good if you can make an update on how it went afterwards. We need to increase the body of knowledge available.

Try searching on the piercing sub

https://www.reddit.com/r/piercing/search?q=Surgery&restrict_sr=on&include_over_18=on