The band name is fine & angry singing does fit into Metalcore—there are so many subgenres of metal it’s ridiculous. 

Deathcore would be a fun genre as well. Born of Osiris is a band in that category but Metalcore is fine too! 

I am thinking about having my character have a stage name of Petra Antar but I can’t say for sure before finding a picture. I don’t know if anyone else shares this quirk but I can’t construct a character until I find a picture.