"What is the purpose of today's private council meeting, your majesty?" Vita queries Mircea. Mircea had called for an exclusive council meeting including Athos. She had decided on informing the council about the problem disguised as a witch prince who wanted to marry her.
Mircea didn't know the council well; however, she knew they wouldn't fancy taking orders from a foreign witch prince. Moreover, they wouldn't bother themselves with some problem that Faustina had caused. If she played her cards right with them perhaps they would solve her problem for her.
That didn't mean she wouldn't be married. The moment Mircea received that letter she had known she had to marry someone, one way or the other.