Welcome to the Message Forum! You can write here messages, questions, comments etc. on Karita Mattila. I will try to find answers as soon as possible.
There seems to be a fourth performance of Jenufa at the Bavarian State Opera on 14th April with Karita as Kostelnicka: https://www.staatsoper.de/stueckinfo/jenufa/2017-07-14-19-00.html
I think you have mistaken with the date. It's 14 of July, not March. Even the link you wrote suggests it.
Sorry, my bad! I was too careless to take a look at the month. It really is 14th July. Anyhow, toi toi for Karita for her performances now and later!