***Was she a prosecutor? A judge? A witness?***
Her Facebook page, I believe
https://www.facebook.com/orsolya.gaal.9
says “Studied at Budapest Business School College of International Management and Business”... so not prosecutor or judge.
I tend to think the texts are red herrings and that a family member did it, but if not, perhaps the killer seeks revenge for something that happened in Hungary. Was the victim by chance Roma?