I did eventually kill Matka. I did it while frail and actually died at the end and had to run back to claim the v-blood. It took entirely too many tries over a number of hours. The only pointer I have for anyone else struggling is to analyze the fighting arena and utilize the extra space available to the west of the boss area. Two sets of trees in that direction make the arena seem much smaller. My game’s difficulty is just regular. Nothing additional, and nothing less.