I must be missing something here. Why would ANYONE jump in line to call a bluff? You'd be risking at min 25% of your dice, or worse case all of them. To what advantage would you do this?
I can maybe see it at higher player counts, but lower ones seems even more foolish. Unless maybe you see an opening to win, but you need to lose a die and end the game quickly?
That could be a reason yes. My son wanted the game to end so he called bluff every signle time.
There can be other situations as well. 3 players. Player one has one die, player two has one die, player three has three dice. Player one says "3 poison". Player two doesn't know if calling bluff would be a good move, but player three might know and can call bluff with zero risk.