I literally had the same experience on my 2nd mastema rag - (my first run for both rags went smoothly)
When mordred failed to land VoF, I almost lost the battle cuz of that one small screwup (only 1 def down landed, if black propaganda missed i probably wouldve lost)
Still won, but with only 2 himes standing (i recorded it halfway but just stopped since it was such a bad run lol)